@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap');

        /* ================= RESET & CƠ BẢN ================= */
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            -webkit-tap-highlight-color: transparent;
        }

        html, body, button, a, input, select, textarea, [role="button"], .nav-btn, .btn-submit, .action-btn-hw {
            touch-action: manipulation;
            -webkit-tap-highlight-color: transparent;
        }

        button, a, .nav-btn, .btn-submit, .action-btn-hw, .btn-quick, .btn-restore, .btn-edit, .btn-delete {
            -webkit-touch-callout: none;
            -webkit-user-select: none;
            user-select: none;
        }

        /* Phản hồi chạm tức thì (Instant Touch Feedback 0ms) */
        button:active, a:active, .nav-btn:active, .btn-submit:active, .action-btn-hw:active {
            transform: scale(0.96) !important;
            transition: transform 0.05s ease !important;
        }

        html, body {
            overflow-x: hidden !important;
            max-width: 100vw !important;
            width: 100% !important;
            touch-action: pan-y;
        }

        body {
            background-color: var(--bg-page); 
            background-image: var(--bg-page-gradient);
            background-attachment: fixed;
            background-size: cover;
            color: var(--text-primary);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            align-items: center;
            overflow-x: hidden !important;
            position: relative;
        }

        /* ================= HEADER ================= */
        /* ================= NAVBAR & HEADER ================= */
        .header {
            position: sticky;
            top: 0;
            left: 0;
            width: 100%;
            z-index: 1000;
            background: var(--header-bg, rgba(3, 8, 29, 0.7));
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--header-border, rgba(255, 255, 255, 0.05));
            padding: 12px 24px;
            padding-top: calc(constant(safe-area-inset-top, 0px) + 12px);
            padding-top: calc(env(safe-area-inset-top, 0px) + 12px);
            padding-left: calc(constant(safe-area-inset-left, 0px) + 24px);
            padding-left: calc(env(safe-area-inset-left, 0px) + 24px);
            padding-right: calc(constant(safe-area-inset-right, 0px) + 24px);
            padding-right: calc(env(safe-area-inset-right, 0px) + 24px);
            display: flex;
            align-items: center;
        }
        
        .nav-container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 20px;
        }
        
        .nav-left {
            display: flex;
            align-items: center;
            gap: 16px;
        }
        
        .nav-logo {
            width: 38px;
            height: 38px;
        }
        
        .nav-right {
            display: flex;
            align-items: center;
            gap: 12px;
            margin-left: auto;
        }
        
        /* Navigation Buttons */
        .nav-btn {
            background: var(--bg-input, rgba(255, 255, 255, 0.03));
            color: var(--nav-btn-text, #E2E8F0);
            border: 1px solid var(--border-card, rgba(255, 255, 255, 0.08));
            padding: 10px 20px;
            border-radius: 30px;
            font-size: 13.5px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            display: inline-flex;
            align-items: center;
            gap: 8px;
            text-decoration: none;
        }
        
        .nav-btn i {
            font-size: 14px;
        }
        
        .nav-btn:hover {
            background: var(--nav-hover-bg, rgba(255, 255, 255, 0.08));
            border-color: var(--border-color, rgba(255, 255, 255, 0.2));
            color: var(--text-primary);
            transform: translateY(-1px);
        }
        
        .nav-btn.active {
            background: var(--nav-active-bg, var(--btn-bg));
            border: 1px solid var(--nav-active-border, var(--color-primary));
            color: var(--nav-active-text, var(--btn-text));
            font-weight: 700;
            box-shadow: var(--shadow-primary);
        }

        /* Nút Tải App trên Header */
        .nav-install-btn {
            display: inline-flex !important;
            align-items: center !important;
            justify-content: center !important;
            gap: 7px !important;
            background: linear-gradient(135deg, #2563EB 0%, #1D4ED8 100%) !important;
            color: #FFFFFF !important;
            border: 1px solid rgba(255, 255, 255, 0.3) !important;
            padding: 0 16px !important;
            height: 38px !important;
            min-height: 38px !important;
            border-radius: 30px !important;
            font-size: 13px !important;
            font-weight: 700 !important;
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif !important;
            cursor: pointer !important;
            box-shadow: 0 4px 14px rgba(37, 99, 235, 0.28) !important;
            transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1) !important;
            text-decoration: none !important;
            white-space: nowrap !important;
            flex-shrink: 0 !important;
            user-select: none !important;
            -webkit-tap-highlight-color: transparent !important;
        }

        .nav-install-btn i {
            font-size: 13.5px !important;
            color: #FFFFFF !important;
            line-height: 1 !important;
        }

        .nav-install-btn:hover {
            background: linear-gradient(135deg, #1D4ED8 0%, #1E40AF 100%) !important;
            box-shadow: 0 6px 18px rgba(37, 99, 235, 0.4) !important;
            transform: translateY(-1px) !important;
        }

        .nav-install-btn:active {
            transform: scale(0.95) !important;
            box-shadow: 0 2px 8px rgba(37, 99, 235, 0.2) !important;
        }

        .is-pwa-standalone .nav-install-btn {
            display: none !important;
        }
        
        .header-text h1 { font-size: 18px; font-weight: 700; color: var(--text-primary, #1E293B); margin-bottom: -2px; letter-spacing: -0.5px;}
        .header-text p { font-size: 11px; color: var(--text-secondary); font-weight: 500;}

        /* === NAVBAR MOBILE BASE === */
        .hamburger-btn {
            display: none !important;
            background: none;
            border: none;
            color: var(--nav-btn-text, #1E293B);
            font-size: 22px;
            cursor: pointer;
            padding: 10px;
            min-width: 44px;
            min-height: 44px;
            align-items: center;
            justify-content: center;
            border-radius: 10px;
            transition: background 0.2s;
        }
        .hamburger-btn:hover {
            background: var(--nav-hover-bg, rgba(59, 130, 246, 0.08));
        }

        .mobile-nav-dropdown {
            display: none !important;
            position: absolute;
            top: 100%;
            right: 0;
            left: 0;
            background: var(--header-bg, rgba(255, 255, 255, 0.98));
            border-bottom: 1px solid var(--header-border, #DBEAFE);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            box-shadow: 0 10px 25px rgba(0, 0, 0, 0.08);
            z-index: 998;
            padding: 8px;
            flex-direction: column;
            gap: 4px;
        }
        .mobile-nav-dropdown.open {
            display: flex !important;
        }

        @media (min-width: 769px) {
            .hamburger-btn {
                display: none !important;
            }
            .mobile-nav-dropdown {
                display: none !important;
            }
            .nav-right {
                display: flex !important;
            }
        }

        .mobile-nav-item {
            padding: 13px 16px;
            border-radius: 10px;
            color: var(--nav-btn-text, #1E293B);
            text-decoration: none;
            font-size: 15px;
            font-weight: 600;
            display: flex;
            align-items: center;
            gap: 14px;
            min-height: 48px;
            transition: background 0.2s, color 0.2s;
        }
        .mobile-nav-item:hover,
        .mobile-nav-item.active {
            background: var(--nav-active-bg, #EFF6FF);
            color: var(--nav-active-text, #2563EB);
        }
        .mobile-nav-item i {
            width: 20px;
            text-align: center;
        }

        /* Intro Card on Home */
        .intro-card {
            background: var(--bg-card);
            border: 1px solid var(--border-card);
            border-radius: 20px;
            padding: 30px;
            max-width: 650px;
            margin: 20px auto 40px auto;
            text-align: center;
            backdrop-filter: blur(10px);
            -webkit-backdrop-filter: blur(10px);
            box-shadow: var(--shadow-card);
            z-index: 10;
            position: relative;
        }
        
        .intro-card h2 {
            font-size: 20px;
            font-weight: 700;
            color: var(--text-primary);
            margin-bottom: 12px;
            letter-spacing: -0.3px;
        }
        
        .intro-card p {
            font-size: 14px;
            color: var(--text-secondary);
            line-height: 1.6;
            margin-bottom: 24px;
        }
        
        .intro-buttons {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 16px;
        }
        
        .btn-intro {
            padding: 12px 24px;
            border-radius: 30px;
            font-size: 14px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s;
            display: inline-flex;
            align-items: center;
            gap: 8px;
            border: 1px solid transparent;
        }
        
        .btn-intro.btn-purple {
            background: var(--btn-bg);
            color: var(--btn-text);
            box-shadow: var(--shadow-primary);
        }
        
        .btn-intro.btn-purple:hover {
            transform: translateY(-2px);
            box-shadow: var(--shadow-primary);
        }
        
        .btn-intro.btn-dark {
            background: rgba(255, 255, 255, 0.05);
            color: #FFFFFF;
            border-color: rgba(255, 255, 255, 0.1);
        }
        
        .btn-intro.btn-dark:hover {
            background: rgba(255, 255, 255, 0.1);
            transform: translateY(-2px);
        }

        .page-section {
            width: 100%;
            display: flex;
            flex-direction: column;
            align-items: center;
            animation: fadeIn 0.4s ease-in-out;
        }

        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(10px); }
            to { opacity: 1; transform: translateY(0); }
        }
        
        @media (max-width: 768px) {
            .header {
                padding: 12px 16px;
                padding-top: max(48px, calc(constant(safe-area-inset-top, 0px) + 12px));
                padding-top: max(48px, calc(env(safe-area-inset-top, 0px) + 12px));
                padding-left: calc(constant(safe-area-inset-left, 0px) + 16px);
                padding-left: calc(env(safe-area-inset-left, 0px) + 16px);
                padding-right: calc(constant(safe-area-inset-right, 0px) + 16px);
                padding-right: calc(env(safe-area-inset-right, 0px) + 16px);
            }
            .nav-container {
                gap: 12px;
                align-items: center;
            }
            .nav-btn {
                padding: 10px 12px;
                font-size: 13px;
                min-height: 42px;
            }
            .intro-buttons {
                flex-direction: column;
                gap: 12px;
            }
            .btn-intro {
                width: 100%;
                justify-content: center;
            }
        }

        /* ≤ 768px: ẩn nav-right, hiện hamburger */
        @media (max-width: 768px) {
            .header {
                padding: 10px 16px !important;
                padding-top: calc(constant(safe-area-inset-top, 0px) + 10px) !important;
                padding-top: calc(env(safe-area-inset-top, 0px) + 10px) !important;
                padding-left: calc(constant(safe-area-inset-left, 0px) + 16px) !important;
                padding-left: calc(env(safe-area-inset-left, 0px) + 16px) !important;
                padding-right: calc(constant(safe-area-inset-right, 0px) + 16px) !important;
                padding-right: calc(env(safe-area-inset-right, 0px) + 16px) !important;
                width: 100% !important;
                box-sizing: border-box !important;
            }
            .nav-container {
                width: 100% !important;
                flex-direction: row !important;
                justify-content: space-between !important;
                align-items: center !important;
                gap: 12px !important;
                box-sizing: border-box !important;
            }
            .nav-left {
                width: auto !important;
                gap: 10px !important;
                min-width: 0 !important;
                margin-bottom: 0 !important;
            }
            .nav-logo {
                width: 34px !important;
                height: 34px !important;
                flex-shrink: 0 !important;
            }
            .header-text h1 {
                font-size: 15.5px !important;
                white-space: nowrap !important;
                overflow: hidden !important;
                text-overflow: ellipsis !important;
                margin: 0 !important;
                line-height: 1.2 !important;
            }
            .header-text p {
                display: none !important;
            }
            .nav-right {
                display: none !important;
            }
            .hamburger-btn {
                display: flex !important;
                flex-shrink: 0 !important;
            }
            .mobile-nav-dropdown.open {
                display: flex !important;
            }
        }

        /* ================= TRANG TRÍ 3D & ANIMATION ================= */
        .decor { position: absolute; z-index: 1; pointer-events: none; }
        .planet-left { top: 12%; left: 6%; width: 110px; animation: float 6s infinite ease-in-out; filter: drop-shadow(0 0 20px rgba(0, 200, 255, 0.2)); z-index: 1; pointer-events: none; }
        .planet-right { top: 15%; right: 8%; width: 90px; animation: float 5s infinite ease-in-out 1s; filter: drop-shadow(0 0 20px rgba(142, 77, 255, 0.3)); z-index: 1; pointer-events: none; }
        .rocket { top: 22%; right: 18%; width: 60px; animation: fly 8s infinite linear; filter: drop-shadow(0 0 15px rgba(255, 100, 100, 0.4)); transform: rotate(45deg); z-index: 1; pointer-events: none; }
        
        .star { position: absolute; background: #fff; border-radius: 50%; box-shadow: 0 0 10px #fff, 0 0 20px #fff; animation: twinkle 2s infinite alternate; z-index: 1; pointer-events: none; }
        .star-1 { top: 25%; left: 22%; width: 4px; height: 4px; }
        .star-2 { top: 35%; right: 28%; width: 5px; height: 5px; animation-delay: 0.5s;}
        .star-3 { top: 15%; right: 40%; width: 3px; height: 3px; animation-delay: 1s;}
        .star-4 { top: 50%; left: 10%; width: 3px; height: 3px; animation-delay: 0.3s;}

        .star-icon { position: absolute; color: #FFD23F; filter: drop-shadow(0 0 10px rgba(255, 210, 63, 0.8)); animation: float 4s infinite ease-in-out; z-index: 1; pointer-events: none;}
        .star-icon-1 { top: 40%; left: 4%; font-size: 24px; }
        .star-icon-2 { top: 12%; right: 30%; font-size: 18px; }
        .star-icon-3 { bottom: 25%; right: 12%; font-size: 30px; animation-delay: 1.5s; transform: rotate(15deg); }
        .star-icon-4 { bottom: 30%; left: 20%; font-size: 35px; color: #FF9999; filter: drop-shadow(0 0 15px rgba(255, 153, 153, 0.6)); transform: rotate(-15deg); }

        @keyframes float { 0%, 100% { transform: translateY(0px); } 50% { transform: translateY(-15px); } }
        @keyframes twinkle { 0% { opacity: 0.3; transform: scale(0.8); } 100% { opacity: 1; transform: scale(1.3); } }
        @keyframes fly { 0% { transform: translate(0, 0) rotate(45deg); opacity: 0;} 10% { opacity: 1; } 90% { opacity: 1; } 100% { transform: translate(-300px, -300px) rotate(45deg); opacity: 0;} }

        /* ================= VÙNG NỘI DUNG CHÍNH ================= */
        .main-container {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: flex-start;
            width: 100%;
            max-width: 1200px;
            margin-top: 80px;
            padding: 0 20px;
            position: relative;
            z-index: 20;
            overflow-x: hidden !important;
            box-sizing: border-box !important;
        }

        .badge {
            background: #EFF6FF;
            border: 1px solid #BFDBFE;
            padding: 6px 18px;
            border-radius: 30px;
            font-size: 11px;
            font-weight: 700;
            color: #2563EB;
            display: flex;
            align-items: center;
            gap: 8px;
            margin-bottom: 15px;
            letter-spacing: 0.5px;
            box-shadow: 0 2px 10px rgba(59, 130, 246, 0.1);
            text-transform: uppercase;
        }
        .badge span { color: #2563EB; font-size: 14px; }

        .main-title {
            text-align: center;
            font-size: 56px;
            font-weight: 900; 
            line-height: 1.1;
            margin-bottom: 10px;
            letter-spacing: -2px;
            color: var(--text-primary);
        }
        .main-title .highlight { 
            color: var(--color-accent-kpi, #2563EB); 
            text-shadow: none;
        }
        
        .sub-title {
            color: var(--text-secondary);
            font-size: 16px;
            text-align: center;
            margin-bottom: 25px;
            font-weight: 400;
            line-height: 1.5;
            letter-spacing: -0.2px;
        }

        /* ================= KHUNG TÌM KIẾM ================= */
        .search-card {
            background: var(--bg-card);
            border: 1px solid var(--border-card);
            border-radius: 20px;
            padding: 25px 40px;
            width: 100%;
            max-width: 750px;
            box-shadow: var(--shadow-card);
            backdrop-filter: blur(16px);
            -webkit-backdrop-filter: blur(16px);
            position: relative;
            z-index: 30;
            margin-bottom: 20px;
        }
        
        .search-title {
            font-size: 16px;
            font-weight: 600;
            color: var(--text-primary);
            margin-bottom: 15px;
            display: flex;
            align-items: center;
            gap: 12px;
            letter-spacing: -0.3px;
        }
        .search-title i { color: var(--color-primary); font-size: 18px;}

        .input-wrapper {
            position: relative;
            background: var(--bg-input);
            border: 1px solid var(--border-card);
            border-radius: 12px;
            box-shadow: inset 0 1px 3px rgba(0,0,0,0.05);
            display: flex;
            align-items: center;
        }
        
        .input-icon { 
            position: absolute;
            left: 20px;
            top: 50%;
            transform: translateY(-50%);
            opacity: 0.7;
            font-size: 16px;
            color: var(--color-primary);
            z-index: 2;
            pointer-events: none;
        }
        
        .input-wrapper input {
            width: 100%;
            background: transparent;
            border: none;
            color: var(--text-primary);
            font-size: 14px;
            outline: none;
            padding: 16px 110px; /* Symmetrical padding to center text exactly relative to the wrapper */
            font-family: 'Inter', sans-serif;
            font-weight: 500;
            text-align: center;
            z-index: 1;
        }
        .input-wrapper input::placeholder { color: var(--text-muted); font-weight: 400;}

        .btn-submit {
            background: var(--btn-bg);
            color: var(--btn-text);
            border: none;
            padding: 0 25px;
            height: 45px;
            border-radius: 25px;
            font-weight: 600;
            font-size: 14px;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            transition: all 0.3s;
            box-shadow: var(--shadow-primary);
            white-space: nowrap;
            letter-spacing: -0.2px;
        }
        .btn-submit:hover {
            box-shadow: var(--shadow-primary);
            transform: translateY(-2px);
        }

        /* Chỉ định vị tuyệt đối cho nút Tiếp tục bên trong ô nhập SĐT */
        .input-wrapper .btn-submit {
            position: absolute;
            right: 6px;
            top: 50%;
            transform: translateY(-50%);
            z-index: 2;
        }
        .input-wrapper .btn-submit:hover {
            transform: translateY(-50%) translateY(-2px);
        }

        .error-msg { color: #FF4D4D; font-size: 13px; margin-top: 10px; display: none; text-align: center; font-weight: 500;}
        .loading-text { display: none; color: var(--color-primary); margin-top: 10px; font-style: italic; font-size: 13px; text-align: center;}

        /* ================= MẶT BÀN & NHÂN VẬT (CHỈNH KÍCH THƯỚC LỚN HƠN) ================= */
        .desk-surface {
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 150%;
            height: 350px;
            background: radial-gradient(ellipse at top, #0B124E 0%, #03081D 70%);
            border-top: 1px solid rgba(142, 77, 255, 0.4);
            border-radius: 50% 50% 0 0 / 100px 100px 0 0;
            z-index: 5;
            box-shadow: inset 0 30px 80px rgba(0,0,0,0.8);
        }

        .character { 
            position: absolute; 
            z-index: 25; 
            filter: drop-shadow(0 30px 30px rgba(0,0,0,0.7)); /* Tăng viền bóng đổ để nhân vật có khối sâu hơn */
            transition: 0.3s;
        }
        
        /* Chỉnh cậu bé to lên, sát lề trái, hạ thấp xuống ngồi thẳng lên mép bàn */
        .char-boy { 
            left: -1%; 
            bottom: 10px; 
            width: 450px; 
        }
        
        /* Chỉnh cô bé to lên, sát lề phải, hạ thấp xuống */
        .char-girl { 
            right: 0%; 
            bottom: 30px; 
            width: 380px; 
        }

        /* ================= 4 THẺ TÍNH NĂNG ================= */
        .features-container {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 16px;
            width: 100%;
            max-width: 1000px;
            position: relative;
            z-index: 40;
            margin-top: 15px; 
            padding-bottom: 20px; 
        }

        .feature-card {
            background: var(--bg-card);
            border: 1px solid var(--border-card);
            border-radius: 16px;
            padding: 20px 15px; 
            text-align: center;
            transition: all 0.3s ease;
            box-shadow: var(--shadow-card);
            backdrop-filter: blur(10px);
            position: relative;
            overflow: hidden;
        }
        .feature-card::before {
            content: ''; position: absolute; top: 0; left: 0; width: 100%; height: 100%;
            background: linear-gradient(180deg, rgba(255,255,255,0.03) 0%, transparent 50%);
            pointer-events: none;
        }

        .feature-card:hover { 
            transform: translateY(-5px); 
            background: var(--bg-card-alt);
        }
        .card-purple:hover { border-color: var(--color-primary); box-shadow: var(--shadow-primary); }
        .card-blue:hover { border-color: #3399FF; box-shadow: 0 15px 40px rgba(51, 153, 255, 0.2); }
        .card-green:hover { border-color: #00CC66; box-shadow: 0 15px 40px rgba(0, 204, 102, 0.2); }
        .card-orange:hover { border-color: #FF9933; box-shadow: 0 15px 40px rgba(255, 153, 51, 0.2); }

        .icon-circle {
            width: 50px; 
            height: 50px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 12px; 
            font-size: 22px;
            color: #fff;
        }
        
        .icon-purple { background: var(--btn-bg); box-shadow: var(--shadow-primary); }
        .icon-blue { background: linear-gradient(135deg, #33ccff, #0066ff); box-shadow: 0 0 25px rgba(0,102,255,0.4); }
        .icon-green { background: linear-gradient(135deg, #33ff99, #009933); box-shadow: 0 0 25px rgba(0,153,51,0.4); }
        .icon-orange { background: linear-gradient(135deg, #ffcc66, #ff6600); box-shadow: 0 0 25px rgba(255,102,0,0.4); }

        .feature-card h3 { font-size: 15px; margin-bottom: 6px; color: var(--text-primary); font-weight: 700; letter-spacing: -0.2px;}
        .feature-card p { font-size: 12px; color: var(--text-secondary); line-height: 1.4; font-weight: 400;}

        /* ================= KHU VỰC KẾT QUẢ ================= */
        #resultBox {
            width: 100%;
            max-width: 1000px;
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 20px;
            padding: 30px;
            margin-top: 20px;
            position: relative;
            z-index: 50;
            box-shadow: var(--shadow-card);
            backdrop-filter: blur(25px);
            display: none;
        }
        
        #resultBox h3 { color: var(--text-heading); font-size: 24px; margin-bottom: 20px; text-align: center; font-weight: 800; letter-spacing: -0.5px;}
        #resultBox h3 .student-name { color: var(--color-primary); }
        .result-section { background: var(--bg-card-alt); padding: 20px; border-radius: 16px; margin-bottom: 20px; border: 1px solid var(--border-card); }
        .result-section h4 { color: var(--color-primary); margin-bottom: 15px; font-size: 16px; display: flex; align-items: center; gap: 10px; font-weight: 600; letter-spacing: -0.3px;}
        
        .table-wrapper { width: 100%; overflow-x: auto; border-radius: 12px; }
        table { width: 100%; border-collapse: collapse; min-width: 800px; }
        th, td { border-bottom: 1px solid var(--border-card); padding: 12px 16px; text-align: left; font-size: 13px; color: var(--text-primary);}
        th { background-color: var(--nav-active-bg); color: var(--text-primary); white-space: nowrap; font-weight: 600;}
        tr:hover td { background-color: var(--nav-hover-bg); }

        /* ===== LỊCH SỬ HỌC TẬP - PH/HS & GIA SƯ (RESPONSIVE KHÔNG THANH CUỘN NGANG) ===== */
        .table-wrapper.desktop-table-view {
            width: 100% !important;
            overflow-x: hidden !important;
            border-radius: 12px;
            box-sizing: border-box;
        }
        .history-table,
        .tutor-history-table {
            width: 100% !important;
            max-width: 100% !important;
            min-width: 0 !important;
            border-collapse: collapse;
            font-family: Inter, sans-serif;
            table-layout: auto;
        }
        .history-table th,
        .tutor-history-table th {
            background: #F0F7FF;
            color: #64748B;
            font-size: 11px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.3px;
            padding: 8px 6px !important;
            text-align: left;
            border-bottom: 2px solid #DBEAFE;
            white-space: nowrap;
            box-sizing: border-box;
        }
        [data-theme="dark"] .history-table th,
        [data-theme="dark"] .tutor-history-table th {
            background: rgba(30, 41, 59, 0.7);
            color: #94A3B8;
            border-bottom: 2px solid rgba(59, 130, 246, 0.3);
        }
        .history-row td,
        .tutor-history-row td,
        .history-table td,
        .tutor-history-table td {
            padding: 8px 6px !important;
            border-bottom: 1px solid var(--border-card, #F1F5F9);
            font-size: 12.5px;
            color: var(--text-primary, #475569);
            vertical-align: middle;
            box-sizing: border-box;
        }
        .history-row:hover,
        .tutor-history-row:hover,
        .history-table tr:hover td,
        .tutor-history-table tr:hover td {
            background-color: var(--nav-hover-bg, #F8FAFF);
        }
        .history-table .cell-noidung,
        .tutor-history-table .cell-noidung {
            min-width: 100px;
            white-space: normal !important;
            word-break: break-word;
            overflow-wrap: break-word;
            line-height: 1.35;
            color: var(--text-heading, #1E293B);
            font-weight: 500;
            font-size: 12px;
        }
        .history-table .cell-nhanxet,
        .tutor-history-table .cell-nhanxet {
            min-width: 120px;
            white-space: normal !important;
            word-break: break-word;
            overflow-wrap: break-word;
            line-height: 1.35;
            font-size: 12px;
            color: var(--text-primary, #334155);
        }
        
        .bt-item {
            display: flex; justify-content: space-between; align-items: center;
            padding: 12px 0; border-bottom: 1px dashed var(--border-color);
        }
        .bt-item:last-child { border-bottom: none; padding-bottom: 0;}
        
        a.btn-download { display: inline-flex; align-items: center; gap: 8px; padding: 8px 16px; background: var(--nav-hover-bg); color: var(--text-primary); text-decoration: none; border-radius: 20px; font-size: 13px; transition: 0.3s; font-weight: 600; border: 1px solid var(--color-primary);}
        a.btn-download:hover { background: var(--color-primary); color: var(--btn-text); box-shadow: var(--shadow-primary); transform: translateY(-2px);}
        
        .btn-back { width: 100%; padding: 14px; background: transparent; border: 1px solid var(--color-primary); color: var(--text-primary); border-radius: 25px; font-weight: 600; font-size: 15px; cursor: pointer; transition: 0.3s; display: flex; justify-content: center; align-items: center; gap: 10px; letter-spacing: -0.2px;}
        .btn-back:hover { background: var(--nav-active-bg); box-shadow: none;}
/* ================= RESPONSIVE (TỐI ƯU HÓA MOBILE CHUẨN UI/UX) ================= */
        @media (max-width: 1024px) {
            .char-boy { width: 220px; left: 2%; bottom: 100px;}
            .char-girl { width: 190px; right: 2%; bottom: 110px;}
            .main-title { font-size: 46px; }
            .features-container { grid-template-columns: repeat(2, 1fr); max-width: 600px;}
        }

        @media (max-width: 768px) {
            /* Ẩn 3D, hành tinh trang trí, rocket, và các ngôi sao để tránh đè giao diện hoặc chặn click trên mobile */
            .char-boy, .char-girl, .desk-surface, .star-icon, .decor { display: none !important; }
            
            .main-title { font-size: 32px; letter-spacing: -1px;}
            .search-card { padding: 25px 20px; border-radius: 16px;}

            /* 1. XỬ LÝ KHUNG TÌM KIẾM BẰNG GRID */
            .input-wrapper {
                display: grid;
                grid-template-columns: auto 1fr;
                grid-template-rows: auto auto;
                gap: 15px;
                background: transparent;
                border: none;
                padding: 0;
                box-shadow: none;
            }
            
            /* Cố định Icon nằm lọt thỏm vào bên trong ô Input */
            .input-icon {
                position: static;
                transform: none;
                grid-column: 1;
                grid-row: 1;
                align-self: center;
                margin-left: 18px;
                z-index: 2; /* Nổi lên trên nền của input */
                font-size: 18px;
                color: #8E95BE;
            }
            
            /* Ô Input trải dài và thụt lề trái để chừa chỗ cho Icon */
            .input-wrapper input {
                grid-column: 1 / 3;
                grid-row: 1;
                background: var(--bg-input);
                border: 1px solid var(--border-card);
                color: var(--text-primary);
                border-radius: 12px;
                padding: 14px 45px; 
                width: 100%;
                font-size: 15px;
                text-align: center;
            }
            
            .input-wrapper input:focus {
                border-color: var(--color-primary);
                box-shadow: var(--shadow-primary);
            }
            
            /* Đẩy nút bấm xuống hàng thứ 2, full 100% width */
            .btn-submit {
                position: static;
                transform: none;
                grid-column: 1 / 3;
                grid-row: 2;
                width: 100%;
                height: 48px;
                font-size: 15px;
            }
            .input-wrapper .btn-submit {
                position: static;
                transform: none;
            }
            .input-wrapper .btn-submit:hover {
                transform: translateY(-2px);
            }

            /* 2. XỬ LÝ 4 THẺ TÍNH NĂNG DẠNG DANH SÁCH NGANG */
            .features-container { 
                grid-template-columns: 1fr; 
                padding: 0; 
                gap: 12px;
            }
            .feature-card { 
                padding: 15px; 
                display: flex; 
                align-items: center; 
                text-align: left; 
                gap: 15px;
            }
            .icon-circle { 
                margin: 0; 
                flex-shrink: 0; 
                width: 45px; 
                height: 45px; 
                font-size: 18px;
            }
            .feature-card h3 { 
                margin-bottom: 4px; 
                font-size: 15px;
            }
            .tutor-header {
                flex-direction: column !important;
                align-items: center !important;
                text-align: center !important;
                justify-content: center !important;
                gap: 14px !important;
                padding: 20px 16px !important;
                border-radius: 18px !important;
                width: 100% !important;
                box-sizing: border-box !important;
            }
            .tutor-header > div:first-child {
                width: 100% !important;
                text-align: center !important;
            }
            .tutor-header h2 {
                font-size: 20px !important;
                text-align: center !important;
            }
            .tutor-header p {
                font-size: 13px !important;
                text-align: center !important;
            }
            .tutor-header > div:last-child {
                width: 100% !important;
                justify-content: center !important;
                display: flex !important;
                gap: 10px !important;
                flex-wrap: wrap !important;
            }
            .tutor-header > div:last-child button {
                flex: 1 1 120px !important;
                max-width: 170px !important;
                padding: 10px 14px !important;
                font-size: 13px !important;
                justify-content: center !important;
            }
            .schedule-section {
                padding: 18px 14px !important;
                border-radius: 18px !important;
                width: 100% !important;
                box-sizing: border-box !important;
            }
            .schedule-section h3 {
                font-size: 16px !important;
                text-align: center !important;
                justify-content: center !important;
            }
            .student-buttons-container {
                justify-content: center !important;
                gap: 8px !important;
                width: 100% !important;
                box-sizing: border-box !important;
                padding: 0 !important;
            }
            .student-btn {
                padding: 9px 16px !important;
                font-size: 13.5px !important;
                border-radius: 25px !important;
            }
            #resultBox, #tutorDashboardBox, #adminDashboardBox {
                width: 100% !important;
                max-width: 100% !important;
                margin: 0 auto 30px auto !important;
                padding: 0 12px !important;
                padding-top: max(48px, calc(constant(safe-area-inset-top, 0px) + 14px)) !important;
                padding-top: max(48px, calc(env(safe-area-inset-top, 0px) + 14px)) !important;
                padding-left: calc(constant(safe-area-inset-left, 0px) + 12px) !important;
                padding-left: calc(env(safe-area-inset-left, 0px) + 12px) !important;
                padding-right: calc(constant(safe-area-inset-right, 0px) + 12px) !important;
                padding-right: calc(env(safe-area-inset-right, 0px) + 12px) !important;
                box-sizing: border-box !important;
            }
            .main-container {
                width: 100% !important;
                max-width: 100% !important;
                margin: 10px auto 30px auto !important;
                padding: 0 12px !important;
                padding-left: calc(constant(safe-area-inset-left, 0px) + 12px) !important;
                padding-left: calc(env(safe-area-inset-left, 0px) + 12px) !important;
                padding-right: calc(constant(safe-area-inset-right, 0px) + 12px) !important;
                padding-right: calc(env(safe-area-inset-right, 0px) + 12px) !important;
                box-sizing: border-box !important;
                overflow-x: hidden !important;
            }
        }

        /* ================= THÔNG BÁO & DASHBOARD TÓM TẮT ================= */
        .announcement-box {
            border-radius: 16px;
            padding: 20px 24px;
            margin-bottom: 25px;
            display: flex;
            align-items: flex-start;
            gap: 16px;
            transition: all 0.3s ease;
            backdrop-filter: blur(10px);
            position: relative;
            overflow: hidden;
            text-align: left;
        }
        
        .announcement-box.has-msg {
            background: linear-gradient(135deg, rgba(255, 210, 63, 0.12), rgba(255, 102, 0, 0.08));
            border: 1px solid rgba(255, 210, 63, 0.4);
            box-shadow: 0 0 25px rgba(255, 210, 63, 0.15);
        }
        
        .announcement-box.no-msg {
            background: var(--bg-card-alt);
            border: 1px solid var(--border-card);
        }
        
        .announcement-icon {
            font-size: 24px;
            flex-shrink: 0;
            margin-top: 2px;
        }
        
        .announcement-box.has-msg .announcement-icon {
            color: var(--color-primary);
            text-shadow: 0 0 10px rgba(var(--color-primary-rgb), 0.4);
            animation: pulse-bell 2s infinite ease-in-out;
        }
        
        .announcement-box.no-msg .announcement-icon {
            color: var(--text-muted);
            opacity: 0.6;
        }
        
        .announcement-content {
            flex: 1;
        }
        
        .announcement-title {
            font-size: 11px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.5px;
            margin-bottom: 6px;
        }
        
        .announcement-box.has-msg .announcement-title {
            color: var(--color-primary);
        }
        
        .announcement-box.no-msg .announcement-title {
            color: var(--text-secondary);
        }
        
        .announcement-text {
            line-height: 1.6;
        }
        
        .announcement-box.has-msg .announcement-text {
            font-size: 17px;
            font-weight: 600;
            color: var(--text-primary);
        }
        
        .announcement-box.no-msg .announcement-text {
            font-size: 13px;
            font-weight: 400;
            color: var(--text-muted);
            font-style: italic;
        }

        @keyframes pulse-bell {
            0%, 100% { transform: scale(1) rotate(0deg); }
            10% { transform: scale(1.1) rotate(-10deg); }
            20% { transform: scale(1.1) rotate(10deg); }
            30% { transform: scale(1.1) rotate(-10deg); }
            40% { transform: scale(1) rotate(0deg); }
        }

        /* Dashboard Summary Grid */
        .summary-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
            gap: 16px;
            margin-bottom: 25px;
            width: 100%;
        }
        
        .summary-card {
            background: var(--glass-bg, var(--bg-card-alt));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 16px;
            padding: 16px 20px;
            display: flex;
            align-items: center;
            gap: 16px;
            transition: all 0.3s ease;
            backdrop-filter: blur(var(--glass-blur, 18px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 18px));
            text-align: left;
        }
        
        .summary-card:hover {
            transform: translateY(-2px);
            background: var(--nav-active-bg);
            border-color: var(--border-color);
            box-shadow: var(--shadow-card);
        }
        
        .summary-icon {
            width: 48px;
            height: 48px;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 20px;
            color: #fff;
            flex-shrink: 0;
        }
        
        .summary-info {
            display: flex;
            flex-direction: column;
            gap: 4px;
        }
        
        .summary-label {
            font-size: 11px;
            color: var(--text-secondary);
            font-weight: 500;
            white-space: nowrap;
        }
        
        .summary-val {
            font-size: 20px;
            font-weight: 800;
            color: var(--text-primary);
        }
        
        /* Chart container */
        .chart-box {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-color));
            border-radius: 20px;
            padding: 24px;
            margin-bottom: 25px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            text-align: left;
        }
        
        .chart-header {
            display: flex;
            align-items: center;
            gap: 10px;
            margin-bottom: 20px;
        }
        
        .chart-header h4 {
            font-size: 16px;
            color: var(--color-primary);
            font-weight: 600;
            letter-spacing: -0.3px;
        }
        
        .chart-header i {
            color: var(--color-primary);
            font-size: 18px;
        }
        
        .chart-canvas-container {
            position: relative;
            height: 280px;
            width: 100%;
        }

        /* Responsive */
        @media (max-width: 768px) {
            .summary-grid {
                grid-template-columns: 1fr;
                gap: 12px;
            }
            .summary-card {
                padding: 12px 15px;
            }
            .announcement-box.has-msg .announcement-text {
                font-size: 15px;
            }
            .chart-canvas-container {
                height: 220px;
            }
        }

        /* Load More Button */
        .load-more-container {
            text-align: center;
            margin-top: 18px;
            margin-bottom: 5px;
        }
        
        .btn-load-more {
            background: var(--nav-active-bg);
            color: var(--text-heading);
            border: 1px solid var(--border-color);
            padding: 8px 32px;
            border-radius: 20px;
            font-size: 18px;
            font-weight: 800;
            letter-spacing: 1px;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: var(--shadow-primary);
            outline: none;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            line-height: 1;
        }
        
        .btn-load-more:hover {
            background: var(--btn-bg);
            border-color: var(--color-primary);
            box-shadow: var(--shadow-primary);
            transform: translateY(-2px);
            color: var(--btn-text);
        }

        /* Custom Chart Legend & Instruction */
        .chart-legend-wrapper {
            display: flex;
            flex-direction: column;
            align-items: center;
            gap: 8px;
            margin-bottom: 20px;
            width: 100%;
        }
        
        .chart-legend-container {
            display: flex;
            justify-content: center;
            gap: 15px;
            flex-wrap: wrap;
            width: 100%;
        }
        
        .legend-btn {
            background: var(--glass-inner, rgba(255, 255, 255, 0.08));
            border: 1px solid var(--border-card);
            border-radius: 20px;
            padding: 8px 16px;
            color: var(--text-secondary);
            font-size: 13px;
            font-weight: 600;
            cursor: pointer;
            display: flex;
            align-items: center;
            gap: 8px;
            transition: all 0.3s ease;
            outline: none;
        }
        
        .legend-btn:hover {
            background: var(--nav-hover-bg);
            color: var(--text-primary);
        }
        
        .legend-btn.active.btn-dau-gio {
            border-color: var(--color-primary);
            background: var(--nav-active-bg);
            color: var(--color-primary-light);
            box-shadow: var(--shadow-primary);
        }
        
        .legend-btn.active.btn-dinh-ki {
            border-color: var(--color-primary-dark);
            background: var(--nav-active-bg);
            color: var(--text-heading);
            box-shadow: var(--shadow-primary);
        }
        
        .legend-btn.inactive {
            text-decoration: line-through;
            opacity: 0.45;
            background: transparent;
            border-color: var(--border-card);
        }
        
        .legend-dot {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            display: inline-block;
        }
        
        .dot-purple {
            background-color: var(--color-primary);
            box-shadow: var(--shadow-primary);
        }
        
        .dot-yellow {
            background-color: var(--color-accent-kpi, #F59E0B);
            box-shadow: 0 0 8px rgba(var(--color-primary-rgb), 0.4);
        }
        
        .chart-instruction {
            font-size: 12px;
            color: var(--text-muted);
            display: flex;
            align-items: center;
            gap: 6px;
            font-weight: 500;
        }
        
        .chart-instruction i {
            font-size: 13px;
            color: var(--color-primary);
        }


        /* Feedback Section styles */
        .feedback-form-container {
            display: flex;
            flex-direction: column;
            gap: 12px;
            width: 100%;
            margin-top: 10px;
        }
        
        .feedback-form-container textarea {
            width: 100%;
            background: var(--bg-input);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 12px 15px;
            color: var(--text-primary);
            font-size: 14px;
            font-family: 'Inter', sans-serif;
            outline: none;
            resize: vertical;
            transition: all 0.3s ease;
            box-shadow: inset 0 2px 5px rgba(0,0,0,0.5);
        }
        
        .feedback-form-container textarea:focus {
            border-color: var(--color-primary);
            box-shadow: inset 0 2px 5px rgba(0,0,0,0.3), 0 0 10px rgba(var(--color-primary-rgb), 0.15);
        }
        
        .btn-submit-feedback {
            background: var(--btn-bg);
            color: var(--btn-text);
            border: none;
            padding: 12px 24px;
            border-radius: 25px;
            font-weight: 600;
            font-size: 14px;
            cursor: pointer;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            transition: all 0.3s ease;
            box-shadow: 0 0 15px rgba(91, 46, 255, 0.4);
            align-self: flex-end;
        }
        
        .btn-submit-feedback:hover {
            box-shadow: var(--shadow-primary);
            transform: translateY(-2px);
        }
        
        .btn-submit-feedback:disabled {
            background: var(--bg-input);
            color: var(--text-muted);
            border: 1px solid var(--border-card);
            box-shadow: none;
            cursor: not-allowed;
            transform: none;
        }
        
        .feedback-message-status {
            display: none;
            font-size: 13px;
            margin-top: 10px;
            text-align: center;
            font-weight: 500;
        }
        
        .feedback-message-status.success {
            color: #00CC66;
            text-shadow: 0 0 10px rgba(0, 204, 102, 0.3);
        }
        
        .feedback-message-status.error {
            color: #FF4D4D;
            text-shadow: 0 0 10px rgba(255, 77, 77, 0.3);
        }

        /* Badges Container styles */
        .badges-container {
            display: flex;
            justify-content: center;
            gap: 12px;
            flex-wrap: wrap;
            margin-bottom: 20px;
            width: 100%;
        }
        
        .medal-badge {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            padding: 8px 16px;
            border-radius: 30px;
            font-size: 13px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.3px;
            box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
            animation: bounce-in 0.6s ease-out;
        }
        
        .medal-gold {
            background: linear-gradient(135deg, rgba(255, 210, 63, 0.2), rgba(212, 175, 55, 0.1));
            border: 1px solid #FFD23F;
            color: #FFD23F;
            text-shadow: 0 0 5px rgba(255, 210, 63, 0.3);
        }
        
        .medal-silver {
            background: linear-gradient(135deg, rgba(200, 200, 200, 0.2), rgba(160, 160, 160, 0.1));
            border: 1px solid var(--color-primary-light);
            color: var(--color-primary-light);
            text-shadow: none;
        }
        
        .medal-bronze {
            background: linear-gradient(135deg, rgba(205, 127, 50, 0.2), rgba(150, 90, 30, 0.1));
            border: 1px solid #FF9933;
            color: #FF9933;
            text-shadow: 0 0 5px rgba(255, 153, 51, 0.3);
        }
        
        .medal-platinum {
            background: linear-gradient(135deg, rgba(255, 255, 255, 0.25), rgba(142, 77, 255, 0.15));
            border: 1px solid #FFF;
            color: #FFF;
            text-shadow: 0 0 10px rgba(255, 255, 255, 0.5);
            box-shadow: 0 4px 20px rgba(142, 77, 255, 0.5);
        }
        
        .medal-academic {
            background: var(--nav-active-bg);
            border: 1px solid var(--color-primary);
            color: var(--color-primary-light);
            text-shadow: none;
        }

        @keyframes bounce-in {
            0% { transform: scale(0.3); opacity: 0; }
            50% { transform: scale(1.05); }
            70% { transform: scale(0.9); }
            100% { transform: scale(1); opacity: 1; }
        }

        /* Accordion style for mobile */
        .mobile-cards-view {
            display: none;
            width: 100%;
        }
        
        @media (max-width: 768px) {
            .desktop-table-view,
            .table-wrapper.desktop-table-view,
            #tuitionTable,
            #tutorScheduleTable {
                display: none !important;
            }
            .mobile-cards-view,
            #tuitionMobileList,
            #tutorScheduleMobile {
                display: block !important;
            }
        }
        
        .accordion-item {
            background: var(--bg-card-alt);
            border: 1px solid var(--border-card);
            border-radius: 12px;
            margin-bottom: 12px;
            overflow: hidden;
            transition: all 0.3s ease;
        }
        
        
        .accordion-header {
            padding: 16px 18px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            font-weight: 600;
            font-size: 14px;
            user-select: none;
            transition: background-color 0.2s;
        }
        
        .accordion-header:hover {
            background-color: var(--nav-hover-bg);
        }
        
        
        .accordion-header-title {
            display: flex;
            flex-direction: column;
            gap: 5px;
            text-align: left;
        }
        
        .accordion-header-date {
            font-size: 12px;
            color: var(--text-secondary);
            font-weight: 400;
        }
        
        
        .accordion-header-status {
            display: flex;
            align-items: center;
            gap: 10px;
        }
        
        .accordion-header i {
            transition: transform 0.3s ease;
            font-size: 12px;
            color: var(--color-primary);
        }
        
        
        .accordion-item.active .accordion-header i {
            transform: rotate(180deg);
        }
        
        .accordion-body {
            padding: 14px 18px 18px 18px;
            border-top: 1px solid var(--border-card);
            background-color: var(--bg-input);
            text-align: left;
            display: none;
            flex-direction: column;
            gap: 0;
            font-size: 13px;
            animation: fade-down 0.3s ease-out;
        }
        
        @keyframes fade-down {
            0% { opacity: 0; transform: translateY(-5px); }
            100% { opacity: 1; transform: translateY(0); }
        }
        
        
        .accordion-body-row {
            display: flex;
            flex-direction: column;
            gap: 6px;
            border-bottom: 1px dashed var(--border-card);
            padding: 11px 0;
        }

        .accordion-body-row:first-child {
            padding-top: 4px;
        }
        
        .accordion-body-row:last-child {
            border-bottom: none;
            padding-bottom: 4px;
        }
        
        
        .accordion-body-label {
            font-size: 10.5px;
            color: var(--text-secondary);
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.4px;
        }
        
        
        .accordion-body-val {
            color: var(--text-primary);
            line-height: 1.5;
        }

        .accordion-actions {
            display: flex !important;
            flex-direction: row !important;
            align-items: center;
            gap: 10px;
            padding-top: 14px;
            margin-top: 2px;
            width: 100%;
            box-sizing: border-box;
        }

        .accordion-actions .modal-btn {
            flex: 1;
            height: 42px;
            min-height: 42px;
            border-radius: 12px;
            font-size: 13px;
            font-weight: 600;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            margin: 0;
            padding: 0 12px;
            box-sizing: border-box;
            cursor: pointer;
            transition: all 0.2s ease;
        }

        .accordion-actions .modal-btn-secondary {
            background: var(--bg-card);
            color: var(--text-primary);
            border: 1px solid var(--border-card);
        }

        .accordion-actions .modal-btn-secondary:hover {
            background: var(--nav-hover-bg);
        }
        
        
        /* Status Badges */
        .status-badge {
            padding: 4px 10px;
            border-radius: 20px;
            font-size: 11.5px;
            font-weight: 700;
            display: inline-flex;
            align-items: center;
            color: var(--text-primary);
        }
        
        /* Trang thai hoc tap */
        .badge-dahoc {
            background-color: rgba(16, 185, 129, 0.14);
            border: 1px solid rgba(16, 185, 129, 0.35);
            color: var(--text-primary);
        }
        
        .badge-hocbu {
            background-color: rgba(59, 130, 246, 0.14);
            border: 1px solid rgba(59, 130, 246, 0.35);
            color: var(--text-primary);
        }
        
        .badge-nghi {
            background-color: rgba(239, 68, 68, 0.14);
            border: 1px solid rgba(239, 68, 68, 0.35);
            color: var(--text-primary);
        }
        
        /* Danh gia BTVN */
        .badge-hoanthanh {
            background-color: rgba(16, 185, 129, 0.14);
            border: 1px solid rgba(16, 185, 129, 0.35);
            color: var(--text-primary);
        }
        
        .badge-thieu {
            background-color: rgba(245, 158, 11, 0.14);
            border: 1px solid rgba(245, 158, 11, 0.35);
            color: var(--text-primary);
        }

        /* Responsive summary grid handled by auto-fit */


        /* ================= TUTOR DASHBOARD STYLES ================= */
        #tutorDashboardBox {
            width: 100%;
            max-width: 1200px;
            margin: 20px auto 40px auto;
            padding: 0 20px;
            box-sizing: border-box;
            display: none;
            z-index: 50;
            position: relative;
        }

        #tutorDashboardBox.tutor-app-layout {
            max-width: 100% !important;
            width: 100% !important;
            margin: 0 !important;
            padding: 0 !important;
            box-sizing: border-box;
        }

        .tutor-sidebar {
            position: fixed;
            top: 0;
            left: 0;
            bottom: 0;
            width: 240px;
            background: var(--bg-sidebar);
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border-right: 1px solid var(--sidebar-border);
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            padding: 24px 14px 20px 14px;
            z-index: 990;
            box-sizing: border-box;
            overflow: visible;
            scrollbar-width: none;
            -ms-overflow-style: none;
        }

        .tutor-sidebar::-webkit-scrollbar {
            display: none !important;
            width: 0 !important;
            height: 0 !important;
        }

        .tutor-sidebar-brand {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 0 8px 20px 8px;
            border-bottom: 1px solid var(--border-card);
        }

        .sidebar-avatar {
            width: 42px;
            height: 42px;
            border-radius: 12px;
            background: var(--btn-bg);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--btn-text);
            font-size: 19px;
            box-shadow: var(--shadow-primary);
            flex-shrink: 0;
        }

        .sidebar-user-info {
            overflow: hidden;
        }

        .sidebar-user-title {
            font-size: 11px;
            text-transform: uppercase;
            letter-spacing: 0.8px;
            color: var(--text-secondary);
            font-weight: 700;
        }

        .sidebar-user-name {
            font-size: 15px;
            font-weight: 700;
            color: var(--text-heading);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            line-height: 1.3;
        }

        .tutor-sidebar-nav {
            display: flex;
            flex-direction: column;
            gap: 6px;
            margin-top: 18px;
            flex: 1;
            overflow-y: auto;
            overflow-x: hidden;
            scrollbar-width: none;
            -ms-overflow-style: none;
        }

        .tutor-sidebar-nav::-webkit-scrollbar {
            display: none !important;
            width: 0 !important;
            height: 0 !important;
        }

        .sidebar-nav-item {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 12px 14px;
            border-radius: 12px;
            color: var(--text-secondary);
            background: transparent;
            border: 1px solid transparent;
            font-size: 14px;
            font-weight: 600;
            text-decoration: none;
            cursor: pointer;
            transition: all 0.2s ease;
            text-align: left;
            width: 100%;
            box-sizing: border-box;
        }

        .sidebar-nav-item i,
        .sidebar-nav-item .nav-icon-svg {
            font-size: 16px;
            width: 20px;
            height: 18px;
            text-align: center;
            color: var(--text-secondary);
            stroke: currentColor;
            transition: color 0.2s ease;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }

        .sidebar-nav-item:hover {
            background: var(--nav-hover-bg);
            color: var(--text-primary);
            border-color: var(--border-color);
        }

        .sidebar-nav-item:hover i,
        .sidebar-nav-item:hover .nav-icon-svg {
            color: var(--color-primary);
        }

        .sidebar-nav-item.active {
            background: var(--nav-active-bg);
            color: var(--nav-active-text);
            border-color: var(--color-primary);
            font-weight: 700;
            box-shadow: var(--shadow-primary);
        }

        .sidebar-nav-item.active i,
        .sidebar-nav-item.active .nav-icon-svg {
            color: var(--color-primary);
        }

        .tutor-sidebar-footer {
            display: flex;
            flex-direction: column;
            gap: 8px;
            padding-top: 16px;
            border-top: 1px solid var(--border-card);
        }

        .sidebar-footer-btn {
            display: flex;
            align-items: center;
            gap: 10px;
            padding: 10px 14px;
            border-radius: 10px;
            color: var(--text-secondary);
            background: var(--bg-input);
            border: 1px solid var(--border-card);
            font-size: 13px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.2s ease;
            width: 100%;
        }

        .sidebar-footer-btn:hover {
            background: var(--nav-hover-bg);
            color: var(--text-primary);
        }

        .sidebar-footer-btn.logout:hover {
            background: rgba(239, 68, 68, 0.15);
            border-color: rgba(239, 68, 68, 0.4);
            color: #F87171;
        }

        .tutor-sidebar {
            transition: width 0.25s ease, padding 0.25s ease;
        }

        .tutor-main-content {
            margin-left: 240px;
            min-height: 100vh;
            padding: 24px 30px 60px 30px;
            box-sizing: border-box;
            width: calc(100% - 240px);
            transition: margin-left 0.25s ease, width 0.25s ease;
        }

        /* Sidebar Collapse Button & State */
        .sidebar-collapse-btn {
            position: absolute;
            top: 22px;
            right: -13px;
            width: 26px;
            height: 26px;
            border-radius: 50%;
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            color: var(--text-primary);
            display: flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            font-size: 11px;
            transition: all 0.2s ease;
            z-index: 1005;
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.18);
            outline: none;
            padding: 0;
        }

        .sidebar-collapse-btn:hover {
            background: var(--color-primary);
            color: var(--btn-text);
            border-color: var(--color-primary);
            transform: scale(1.12);
        }

        @media (min-width: 769px) {
            .tutor-app-layout.sidebar-collapsed .tutor-sidebar {
                width: 60px !important;
                padding: 24px 8px 20px 8px !important;
                overflow: visible !important;
            }

            .tutor-app-layout.sidebar-collapsed .tutor-sidebar-nav {
                overflow: visible !important;
            }

            .tutor-app-layout.sidebar-collapsed .tutor-main-content {
                margin-left: 60px !important;
                width: calc(100% - 60px) !important;
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-user-info,
            .tutor-app-layout.sidebar-collapsed .sidebar-nav-item span,
            .tutor-app-layout.sidebar-collapsed .sidebar-footer-btn span,
            .tutor-app-layout.sidebar-collapsed .sidebar-theme-btn span {
                display: none !important;
            }

            .tutor-app-layout.sidebar-collapsed .tutor-sidebar-brand {
                padding: 0 0 16px 0 !important;
                justify-content: center;
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-avatar {
                width: 38px;
                height: 38px;
                font-size: 16px;
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-nav-item {
                justify-content: center !important;
                padding: 12px 0 !important;
                position: relative;
                gap: 0 !important;
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-nav-item i,
            .tutor-app-layout.sidebar-collapsed .sidebar-nav-item .nav-icon-svg {
                width: auto;
                font-size: 17px;
                margin: 0;
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-footer-btn,
            .tutor-app-layout.sidebar-collapsed .sidebar-theme-btn {
                justify-content: center !important;
                padding: 10px 0 !important;
                position: relative;
                gap: 0 !important;
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-footer-btn i,
            .tutor-app-layout.sidebar-collapsed .sidebar-theme-btn i {
                font-size: 16px;
                margin: 0;
                width: auto;
            }

            /* Tooltips on hover when collapsed */
            .tutor-app-layout.sidebar-collapsed .sidebar-nav-item::after,
            .tutor-app-layout.sidebar-collapsed .sidebar-footer-btn::after,
            .tutor-app-layout.sidebar-collapsed .sidebar-theme-btn::after {
                content: attr(data-title);
                position: absolute;
                left: calc(100% + 12px);
                top: 50%;
                transform: translateY(-50%);
                background: var(--bg-card);
                border: 1px solid var(--border-color);
                color: var(--text-primary);
                font-size: 12px;
                font-weight: 600;
                padding: 6px 12px;
                border-radius: 8px;
                white-space: nowrap;
                opacity: 0;
                visibility: hidden;
                pointer-events: none;
                transition: opacity 0.15s ease, transform 0.15s ease;
                z-index: 1002;
                box-shadow: 0 4px 20px rgba(0, 0, 0, 0.6);
            }

            .tutor-app-layout.sidebar-collapsed .sidebar-nav-item:hover::after,
            .tutor-app-layout.sidebar-collapsed .sidebar-footer-btn:hover::after,
            .tutor-app-layout.sidebar-collapsed .sidebar-theme-btn:hover::after {
                opacity: 1;
                visibility: visible;
                transform: translateY(-50%) translateX(2px);
            }

            .tutor-app-layout.sidebar-collapsed .tutor-sidebar,
            .tutor-app-layout.sidebar-collapsed .tutor-sidebar * {
                scrollbar-width: none !important;
                -ms-overflow-style: none !important;
            }

            .tutor-app-layout.sidebar-collapsed .tutor-sidebar::-webkit-scrollbar,
            .tutor-app-layout.sidebar-collapsed .tutor-sidebar *::-webkit-scrollbar {
                display: none !important;
                width: 0 !important;
                height: 0 !important;
            }
        }

        /* ===== TUTOR DASHBOARD MOBILE (HEADER + OFFCANVAS DRAWER) ===== */
        .tutor-mobile-header {
            display: none;
            position: sticky;
            top: 0;
            left: 0;
            right: 0;
            height: 56px;
            background: var(--header-bg, var(--bg-card));
            backdrop-filter: blur(20px);
            -webkit-backdrop-filter: blur(20px);
            border-bottom: 1px solid var(--border-color);
            padding: 0 12px;
            align-items: center;
            justify-content: space-between;
            z-index: 990;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
            box-sizing: border-box;
        }

        .mobile-header-left {
            display: flex;
            align-items: center;
            gap: 10px;
            min-width: 0;
        }

        .tutor-mobile-menu-btn {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 40px;
            height: 40px;
            border-radius: 10px;
            background: var(--nav-hover-bg, rgba(59, 130, 246, 0.08));
            border: 1px solid var(--border-color);
            color: var(--text-primary);
            font-size: 18px;
            cursor: pointer;
            flex-shrink: 0;
            transition: all 0.2s;
        }

        .tutor-mobile-menu-btn:hover,
        .tutor-mobile-menu-btn:active {
            background: var(--nav-active-bg);
            color: var(--color-primary);
        }

        .mobile-header-brand {
            display: flex;
            flex-direction: column;
            min-width: 0;
        }

        .mobile-brand-title {
            font-size: 13.5px;
            font-weight: 800;
            color: var(--text-primary);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            line-height: 1.2;
        }

        .mobile-brand-name {
            font-size: 11px;
            font-weight: 600;
            color: var(--color-primary);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
            line-height: 1.2;
        }

        .mobile-header-actions {
            display: flex;
            align-items: center;
            gap: 6px;
            flex-shrink: 0;
        }

        .mobile-action-btn {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 38px;
            height: 38px;
            border-radius: 10px;
            background: var(--nav-hover-bg, rgba(59, 130, 246, 0.08));
            border: 1px solid var(--border-color);
            color: var(--text-primary);
            font-size: 15px;
            cursor: pointer;
            transition: all 0.2s;
        }

        .mobile-action-btn:hover,
        .mobile-action-btn:active {
            background: var(--nav-active-bg);
            color: var(--color-primary);
            border-color: var(--color-primary);
            transform: scale(1.05);
        }

        .mobile-action-btn.logout-btn {
            color: #EF4444;
            background: rgba(239, 68, 68, 0.08);
            border-color: rgba(239, 68, 68, 0.25);
        }

        .mobile-action-btn.logout-btn:hover,
        .mobile-action-btn.logout-btn:active {
            background: rgba(239, 68, 68, 0.18);
            border-color: #EF4444;
            color: #EF4444;
        }

        .sidebar-mobile-close-btn {
            display: none;
        }

        .sidebar-overlay {
            display: none;
        }

        @media (max-width: 768px) {
            .tutor-mobile-header {
                display: flex !important;
            }

            .sidebar-overlay {
                display: block !important;
                position: fixed !important;
                inset: 0 !important;
                background: rgba(15, 23, 42, 0.65) !important;
                backdrop-filter: blur(4px) !important;
                -webkit-backdrop-filter: blur(4px) !important;
                z-index: 1050 !important;
                opacity: 0 !important;
                visibility: hidden !important;
                transition: opacity 0.25s ease, visibility 0.25s ease !important;
                pointer-events: none !important;
            }

            .sidebar-overlay.active {
                opacity: 1 !important;
                visibility: visible !important;
                pointer-events: auto !important;
            }

            .tutor-sidebar {
                position: fixed !important;
                top: 0 !important;
                bottom: 0 !important;
                left: -290px !important;
                right: auto !important;
                width: 275px !important;
                max-width: 85vw !important;
                height: 100vh !important;
                height: 100dvh !important;
                background: var(--bg-sidebar) !important;
                border-right: 1px solid var(--border-card) !important;
                border-top: none !important;
                flex-direction: column !important;
                justify-content: space-between !important;
                align-items: stretch !important;
                padding: 16px 14px 20px 14px !important;
                z-index: 1060 !important;
                box-shadow: 10px 0 35px rgba(0, 0, 0, 0.45) !important;
                transition: left 0.28s cubic-bezier(0.4, 0, 0.2, 1) !important;
                overflow-y: auto !important;
                -webkit-overflow-scrolling: touch !important;
            }

            .tutor-sidebar.mobile-open,
            .tutor-sidebar.open {
                left: 0 !important;
            }

            /* Brand trong drawer mobile */
            .tutor-sidebar-brand {
                display: flex !important;
                align-items: center !important;
                justify-content: space-between !important;
                padding: 4px 6px 14px 6px !important;
                border-bottom: 1px solid var(--border-card) !important;
                margin-bottom: 8px !important;
            }

            .sidebar-mobile-close-btn {
                display: flex !important;
                align-items: center !important;
                justify-content: center !important;
                width: 34px !important;
                height: 34px !important;
                border-radius: 10px !important;
                border: 1px solid var(--border-color) !important;
                background: var(--bg-input) !important;
                color: var(--text-secondary) !important;
                font-size: 16px !important;
                cursor: pointer !important;
                transition: all 0.2s !important;
                flex-shrink: 0 !important;
            }

            .sidebar-mobile-close-btn:hover,
            .sidebar-mobile-close-btn:active {
                background: rgba(239, 68, 68, 0.15) !important;
                color: #EF4444 !important;
                border-color: #EF4444 !important;
            }

            /* Ẩn nút collapse desktop trên mobile */
            .sidebar-collapse-btn {
                display: none !important;
            }

            /* Menu dọc trong drawer mobile */
            .tutor-sidebar-nav {
                display: flex !important;
                flex-direction: column !important;
                justify-content: flex-start !important;
                align-items: stretch !important;
                width: 100% !important;
                margin-top: 6px !important;
                gap: 6px !important;
                overflow-y: auto !important;
                flex: 1 1 auto !important;
            }

            .sidebar-nav-item {
                display: flex !important;
                flex-direction: row !important;
                align-items: center !important;
                justify-content: flex-start !important;
                padding: 12px 14px !important;
                gap: 12px !important;
                border-radius: 12px !important;
                font-size: 13.5px !important;
                font-weight: 600 !important;
                text-align: left !important;
                width: 100% !important;
                min-height: 46px !important;
                box-sizing: border-box !important;
            }

            .sidebar-nav-item span {
                display: inline !important;
                font-size: 13.5px !important;
                white-space: normal !important;
                overflow: visible !important;
                text-overflow: unset !important;
            }

            .sidebar-nav-item i,
            .sidebar-nav-item .nav-icon-svg {
                font-size: 17px !important;
                width: 22px !important;
                height: 22px !important;
                flex-shrink: 0 !important;
            }

            .sidebar-nav-item.active {
                background: var(--nav-active-bg) !important;
                border-color: var(--color-primary) !important;
                color: var(--nav-active-text) !important;
            }

            .sidebar-nav-item.active i,
            .sidebar-nav-item.active .nav-icon-svg {
                color: var(--color-primary) !important;
            }

            /* Footer drawer mobile: HIỆN ĐẦY ĐỦ GIAO DIỆN, TÀI KHOẢN, ĐĂNG XUẤT */
            .tutor-sidebar-footer {
                display: flex !important;
                flex-direction: column !important;
                gap: 8px !important;
                padding-top: 14px !important;
                border-top: 1px solid var(--border-card) !important;
                margin-top: auto !important;
            }

            .tutor-sidebar-footer .sidebar-footer-btn,
            .tutor-sidebar-footer .sidebar-theme-btn {
                display: flex !important;
                align-items: center !important;
                justify-content: flex-start !important;
                gap: 12px !important;
                padding: 11px 14px !important;
                border-radius: 12px !important;
                font-size: 13.5px !important;
                font-weight: 600 !important;
                min-height: 44px !important;
                width: 100% !important;
                box-sizing: border-box !important;
            }

            .tutor-sidebar-footer .sidebar-footer-btn span,
            .tutor-sidebar-footer .sidebar-theme-btn span {
                display: inline !important;
            }

            .tutor-sidebar-footer .sidebar-footer-btn i,
            .tutor-sidebar-footer .sidebar-theme-btn i {
                width: 20px !important;
                text-align: center !important;
            }

            .tutor-main-content {
                margin-left: 0 !important;
                width: 100% !important;
                padding: 14px 12px 40px 12px !important;
                min-height: calc(100vh - 56px) !important;
            }
        }
        
        .tutor-header {
            display: none !important;
            justify-content: space-between;
            align-items: center;
            background: var(--bg-card);
            border: 1px solid var(--border-color);
            border-radius: 20px;
            padding: 20px 30px;
            margin-bottom: 20px;
            box-shadow: var(--shadow-card);
            backdrop-filter: blur(25px);
        }
        
        .tutor-header h2 { color: var(--text-heading); font-size: 24px; font-weight: 800; letter-spacing: -0.5px;}
        .tutor-header p { color: var(--text-secondary); font-size: 14px; margin-top: 5px;}
        
        /* Overview Top Bar & Month Selector */
        .overview-top-bar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
            flex-wrap: wrap;
            gap: 12px;
        }

        .overview-top-title h2 {
            font-size: 20px;
            font-weight: 700;
            color: var(--text-primary);
            margin: 0 0 4px 0;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .overview-top-title p {
            font-size: 13px;
            color: var(--text-secondary);
            margin: 0;
        }

        .month-selector-widget {
            display: inline-flex;
            align-items: center;
            background: var(--btn-bg);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 4px 6px;
            gap: 4px;
            box-shadow: var(--shadow-primary);
        }

        .month-nav-btn {
            background: transparent;
            border: none;
            color: var(--color-primary-light);
            width: 30px;
            height: 30px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 8px;
            cursor: pointer;
            font-size: 13px;
            transition: all 0.2s ease;
            outline: none;
        }

        .month-nav-btn:hover:not(:disabled) {
            background: rgba(255,255,255,0.15);
            color: var(--btn-text);
            transform: scale(1.08);
        }

        .month-nav-btn:disabled {
            opacity: 0.3;
            cursor: not-allowed;
        }

        #overviewMonthDisplay {
            font-size: 14px;
            font-weight: 700;
            color: var(--btn-text);
            min-width: 125px;
            text-align: center;
            letter-spacing: 0.3px;
            user-select: none;
        }

        /* KPI Cards */
        .tutor-kpi-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 16px;
            margin-bottom: 25px;
        }

        .tutor-kpi-card {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 18px;
            padding: 18px 20px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
            box-shadow: var(--shadow-card);
        }

        .tutor-kpi-card:hover {
            transform: translateY(-2px);
            border-color: var(--color-primary);
            box-shadow: var(--shadow-primary);
        }

        .kpi-card-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            gap: 8px;
        }

        .kpi-label {
            font-size: 12px;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.6px;
            color: var(--text-secondary);
        }

        .kpi-icon {
            width: 38px;
            height: 38px;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 17px;
            flex-shrink: 0;
        }

        .kpi-icon.icon-purple {
            background: var(--nav-active-bg);
            color: var(--color-primary);
            border: 1px solid var(--border-color);
        }

        .kpi-icon.icon-green {
            background: rgba(16, 185, 129, 0.15);
            color: #10B981;
            border: 1px solid rgba(16, 185, 129, 0.3);
        }

        .kpi-icon.icon-cyan {
            background: rgba(6, 182, 212, 0.15);
            color: #06B6D4;
            border: 1px solid rgba(6, 182, 212, 0.3);
        }

        .kpi-icon.icon-amber {
            background: rgba(245, 158, 11, 0.15);
            color: #F59E0B;
            border: 1px solid rgba(245, 158, 11, 0.3);
        }

        .kpi-value {
            font-size: 26px;
            font-weight: 800;
            font-family: 'Space Grotesk', 'Inter', sans-serif;
            letter-spacing: -0.5px;
            margin: 12px 0 6px 0;
            line-height: 1.1;
        }

        .text-purple { color: var(--kpi-number-color, var(--text-primary)); }
        .text-green { color: var(--kpi-number-color, var(--text-primary)); }
        .text-cyan { color: var(--kpi-number-color, var(--text-primary)); }
        .text-amber { color: var(--kpi-number-color, var(--text-primary)); }

        .kpi-subtext {
            font-size: 11.5px;
            color: var(--text-muted);
            font-weight: 500;
            display: flex;
            align-items: center;
            gap: 6px;
        }

        /* Overview Charts Row: 2 charts side by side */
        .overview-charts-grid {
            display: grid;
            grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
            gap: 20px;
            margin-bottom: 25px;
            align-items: stretch;
        }

        /* Overview Chart Box */
        .overview-chart-box {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 18px;
            padding: 20px 22px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            box-shadow: var(--glass-shadow, var(--shadow-card));
            box-sizing: border-box;
            width: 100%;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .overview-chart-header {
            display: flex;
            justify-content: space-between;
            align-items: flex-start;
            flex-wrap: wrap;
            gap: 12px;
            margin-bottom: 16px;
        }

        .overview-chart-title {
            color: var(--text-primary);
            font-size: 15px;
            font-weight: 700;
            margin: 0 0 6px 0;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .revenue-big-total-wrap {
            display: flex;
            align-items: baseline;
            gap: 8px;
            flex-wrap: wrap;
        }

        .revenue-big-total {
            font-size: 26px;
            font-weight: 800;
            color: var(--text-heading);
            letter-spacing: -0.5px;
            line-height: 1.1;
        }

        .revenue-big-subtext {
            font-size: 12px;
            color: var(--text-secondary);
            font-weight: 500;
        }

        .overview-chart-filters {
            display: flex;
            align-items: center;
            gap: 8px;
            flex-wrap: wrap;
        }

        .chart-filter-select {
            background: var(--bg-input);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            color: var(--text-primary);
            font-size: 12px;
            font-weight: 600;
            padding: 6px 10px;
            outline: none;
            cursor: pointer;
            transition: all 0.2s ease;
        }

        .chart-filter-select:hover {
            border-color: var(--color-primary);
            background: var(--nav-hover-bg);
        }

        .chart-filter-select option {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        /* Image 2 Style Select Pills */
        .chart-filter-select-img2 {
            background-color: #FFFFFF;
            color: #1E293B;
            border: 1px solid #CBD5E1;
            border-radius: 12px;
            font-size: 13px;
            font-weight: 600;
            padding: 7px 32px 7px 14px;
            outline: none;
            cursor: pointer;
            transition: all 0.2s ease;
            appearance: none;
            -webkit-appearance: none;
            -moz-appearance: none;
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%23334155'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2.5' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
            background-repeat: no-repeat;
            background-position: right 10px center;
            background-size: 13px;
            box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
        }

        .chart-filter-select-img2:hover {
            border-color: #94A3B8;
            box-shadow: 0 2px 6px rgba(0, 0, 0, 0.12);
        }

        .chart-filter-select-img2 option {
            background: #FFFFFF;
            color: #1E293B;
            font-weight: 500;
        }

        [data-theme="dark"] .chart-filter-select-img2 {
            background-color: var(--bg-input, rgba(255, 255, 255, 0.06));
            color: var(--text-primary, #F1F5F9);
            border-color: var(--border-color, rgba(255, 255, 255, 0.15));
            background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%23CBD5E1'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2.5' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
            background-repeat: no-repeat;
            background-position: right 10px center;
            background-size: 13px;
            box-shadow: none;
        }

        [data-theme="dark"] .chart-filter-select {
            background-color: var(--bg-input, rgba(255, 255, 255, 0.06));
            color: var(--text-primary, #F1F5F9);
            border-color: var(--border-color, rgba(255, 255, 255, 0.15));
            color-scheme: dark;
        }

        [data-theme="dark"] .chart-filter-select-img2:hover,
        [data-theme="dark"] .chart-filter-select:hover {
            border-color: var(--primary, #8B5CF6);
        }

        [data-theme="dark"] .chart-filter-select-img2 option,
        [data-theme="dark"] .chart-filter-select option {
            background: var(--bg-page, #0F172A);
            color: var(--text-primary, #F1F5F9);
        }

        .chart-canvas-container {
            position: relative;
            height: 240px;
            width: 100%;
        }

        /* Student Revenue Donut Block */
        #studentRevenueDonutBox {
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .student-revenue-body {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 24px;
            flex: 1;
            margin: auto 0;
            width: 100%;
        }

        .student-donut-wrap {
            position: relative;
            width: 160px;
            height: 160px;
            flex-shrink: 0;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto;
        }

        .student-donut-canvas-container {
            position: relative;
            width: 100%;
            height: 100%;
            display: flex;
            align-items: center;
            justify-content: center;
        }

        .donut-center-total {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            text-align: center;
            pointer-events: none;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
        }

        .donut-center-label {
            font-size: 10px;
            color: var(--text-secondary);
            font-weight: 600;
            text-transform: uppercase;
            letter-spacing: 0.5px;
        }

        .donut-center-value {
            font-size: 14px;
            font-weight: 800;
            color: var(--text-heading);
            line-height: 1.2;
            white-space: nowrap;
        }

        .student-revenue-list {
            display: flex;
            flex-direction: column;
            gap: 8px;
            flex: 1;
            max-width: 420px;
            min-width: 0;
        }

        .student-revenue-item {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 10px;
            padding: 8px 12px;
            background: var(--bg-input);
            border: 1px solid var(--border-card);
            border-radius: 10px;
            transition: all 0.2s ease;
        }

        .student-revenue-item:hover {
            background: var(--nav-active-bg);
            border-color: var(--border-color);
        }

        .student-revenue-left {
            display: flex;
            align-items: center;
            gap: 10px;
            min-width: 0;
        }

        .student-color-dot {
            width: 10px;
            height: 10px;
            border-radius: 50%;
            flex-shrink: 0;
        }

        .student-revenue-info {
            display: flex;
            flex-direction: column;
            min-width: 0;
        }

        .student-revenue-name {
            font-size: 12.5px;
            font-weight: 600;
            color: var(--text-primary);
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .student-revenue-sessions {
            font-size: 10.5px;
            color: var(--text-secondary);
        }

        .student-revenue-amount {
            font-size: 13px;
            font-weight: 700;
            color: var(--text-primary);
            white-space: nowrap;
        }

        .student-revenue-amount.zero {
            color: #6B7280;
        }

        @media (max-width: 680px) {
            .student-revenue-body {
                flex-direction: column !important;
                align-items: center !important;
                justify-content: center !important;
                gap: 16px !important;
                margin: 10px auto !important;
            }
            .student-donut-wrap {
                margin: 0 auto !important;
            }
            .student-revenue-list {
                width: 100% !important;
                max-width: 100% !important;
            }
        }

        @media (max-width: 1024px) {
            .overview-charts-grid {
                grid-template-columns: 1fr !important;
                gap: 16px !important;
            }
        }

        @media (max-width: 768px) {
            .overview-top-bar {
                margin-bottom: 14px !important;
                flex-direction: row !important;
                justify-content: space-between !important;
                align-items: center !important;
            }
            .overview-top-title h2 {
                font-size: 16px !important;
            }
            .overview-top-title p {
                display: none !important;
            }
            .month-selector-widget {
                padding: 3px 4px !important;
            }
            #overviewMonthDisplay {
                font-size: 12.5px !important;
                min-width: 105px !important;
            }
            .month-nav-btn {
                width: 26px !important;
                height: 26px !important;
                font-size: 11px !important;
            }

            .overview-chart-box {
                padding: 16px 14px !important;
                border-radius: 14px !important;
            }
            .revenue-big-total {
                font-size: 22px !important;
            }
            .overview-chart-header {
                flex-direction: column !important;
                gap: 10px !important;
            }
            .overview-chart-filters {
                width: 100%;
                justify-content: flex-start;
            }
            .chart-filter-select {
                font-size: 11px !important;
                padding: 5px 8px !important;
                flex: 1;
                min-width: 80px;
            }
            .chart-canvas-container {
                height: 200px !important;
            }

            .tutor-kpi-grid {
                grid-template-columns: repeat(2, 1fr) !important;
                gap: 10px !important;
                margin-bottom: 18px !important;
            }
            .tutor-kpi-card {
                padding: 14px 12px !important;
                border-radius: 14px !important;
            }
            .kpi-label {
                font-size: 10px !important;
                letter-spacing: 0.3px !important;
            }
            .kpi-icon {
                width: 32px !important;
                height: 32px !important;
                font-size: 14px !important;
                border-radius: 8px !important;
            }
            .kpi-value {
                font-size: 20px !important;
                margin: 8px 0 4px 0 !important;
            }
            .kpi-subtext {
                font-size: 10px !important;
            }
        }

        /* Upcoming Schedule Section */
        .upcoming-schedule-box {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 20px;
            padding: 22px 24px;
            margin-bottom: 25px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            box-shadow: var(--glass-shadow, var(--shadow-card));
        }

        .upcoming-all-schedule-btn:hover {
            background: var(--nav-hover-bg) !important;
            border-color: var(--color-primary) !important;
            color: var(--text-primary) !important;
            box-shadow: var(--shadow-primary);
        }

        .upcoming-days-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 16px;
            margin-top: 14px;
        }

        .upcoming-day-column {
            background: var(--bg-card, #FFFFFF) !important;
            border: 1px solid var(--border-card, #E2E8F0) !important;
            border-radius: 16px;
            padding: 16px;
            display: flex;
            flex-direction: column;
        }

        .upcoming-day-header {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 8px 12px;
            background: var(--nav-active-bg, rgba(59, 130, 246, 0.08)) !important;
            border: 1px solid var(--border-color, #BFDBFE) !important;
            border-radius: 10px;
            margin-bottom: 12px;
            color: var(--text-primary);
            font-size: 13.5px;
            font-weight: 700;
        }

        .upcoming-day-header i {
            color: var(--color-primary);
        }

        .upcoming-items-list {
            display: flex;
            flex-direction: column;
            gap: 10px;
            flex: 1;
        }

        .upcoming-session-card {
            background: var(--nav-active-bg, rgba(59, 130, 246, 0.08)) !important;
            border: 1px solid var(--border-color, #BFDBFE) !important;
            border-radius: 12px;
            padding: 12px 14px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 12px;
            transition: all 0.2s ease;
        }

        .upcoming-session-card:hover {
            background: var(--nav-active-bg, rgba(59, 130, 246, 0.14)) !important;
            border-color: var(--color-primary, #3B82F6) !important;
            transform: translateX(2px);
        }

        .upcoming-session-info {
            display: flex;
            align-items: center;
            gap: 10px;
            flex-wrap: wrap;
        }

        .upcoming-student-tag {
            padding: 4px 10px;
            border-radius: 20px;
            font-size: 12.5px;
            font-weight: 700;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            border: 1px solid var(--border-color, #BFDBFE);
            background: var(--nav-active-bg, rgba(59, 130, 246, 0.12));
            color: var(--text-primary) !important;
        }

        .upcoming-student-tag i {
            color: var(--color-primary);
        }

        .upcoming-subject-badge {
            font-size: 12px;
            color: var(--text-secondary);
            font-weight: 500;
            display: inline-flex;
            align-items: center;
            gap: 5px;
        }

        .upcoming-time-badge {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            background: var(--bg-card, #FFFFFF) !important;
            border: 1px solid var(--border-color, #BFDBFE) !important;
            color: var(--text-primary) !important;
            padding: 4px 12px !important;
            border-radius: 20px !important;
            font-size: 12.5px !important;
            font-weight: 700 !important;
            white-space: nowrap !important;
            box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
        }

        .upcoming-time-badge i {
            color: var(--color-primary);
        }

        .upcoming-empty-card {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            padding: 24px 16px;
            text-align: center;
            color: var(--text-muted);
            font-size: 13px;
            font-style: italic;
            background: var(--nav-active-bg, rgba(59, 130, 246, 0.05)) !important;
            border-radius: 12px;
            border: 1px dashed var(--border-color, #BFDBFE) !important;
            min-height: 80px;
        }

        @media (max-width: 768px) {
            .upcoming-days-grid {
                grid-template-columns: 1fr !important;
                gap: 12px !important;
            }
            .upcoming-schedule-box {
                padding: 16px 14px !important;
            }
            .upcoming-session-card {
                flex-direction: column !important;
                align-items: flex-start !important;
                gap: 8px !important;
            }
            .upcoming-time-badge {
                align-self: flex-start !important;
            }
        }

        /* Diary Section Styles */
        .diary-toolbar {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 20px;
            padding: 20px 24px;
            margin-bottom: 20px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            box-shadow: var(--glass-shadow, var(--shadow-card));
        }

        .diary-filters {
            display: flex;
            align-items: center;
            gap: 15px;
            margin-top: 16px;
            flex-wrap: wrap;
        }

        .diary-filter-item {
            display: flex;
            align-items: center;
            gap: 8px;
            background: var(--glass-inner, rgba(255, 255, 255, 0.35));
            border: 1px solid var(--glass-inner-border, rgba(255, 255, 255, 0.5));
            border-radius: 12px;
            padding: 8px 14px;
        }

        .diary-filter-item label {
            font-size: 12.5px;
            font-weight: 600;
            color: var(--text-secondary);
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .diary-filter-item select {
            background: transparent;
            border: none;
            color: var(--text-heading);
            font-weight: 700;
            font-size: 13.5px;
            outline: none;
            cursor: pointer;
        }

        .diary-filter-item select option {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .diary-count-pill {
            margin-left: auto;
            background: var(--nav-active-bg);
            border: 1px solid var(--border-color);
            color: var(--text-heading);
            font-weight: 700;
            font-size: 12.5px;
            padding: 6px 16px;
            border-radius: 20px;
        }

        /* Comment Box & Inline Edit */
        .diary-comment-box {
            position: relative;
            font-size: 13px;
            line-height: 1.5;
            color: var(--text-primary);
        }

        .diary-comment-text {
            word-break: break-word;
        }

        .btn-comment-toggle {
            background: none;
            border: none;
            color: var(--color-primary);
            font-size: 11.5px;
            font-weight: 700;
            cursor: pointer;
            padding: 2px 4px;
            margin-left: 4px;
            text-decoration: underline;
        }

        .btn-comment-edit {
            background: var(--nav-active-bg);
            border: 1px solid var(--border-color);
            color: var(--text-heading);
            border-radius: 6px;
            padding: 3px 8px;
            font-size: 11px;
            font-weight: 600;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 4px;
            margin-top: 6px;
            transition: all 0.2s ease;
        }

        .btn-comment-edit:hover {
            background: var(--btn-bg);
            color: var(--btn-text);
        }

        .diary-inline-editor {
            display: flex;
            flex-direction: column;
            gap: 6px;
            margin-top: 6px;
        }

        .diary-inline-editor textarea {
            width: 100%;
            min-height: 65px;
            background: var(--bg-input);
            border: 1px solid var(--border-color);
            border-radius: 8px;
            padding: 8px 10px;
            color: var(--text-primary);
            font-size: 12.5px;
            font-family: inherit;
            resize: vertical;
            outline: none;
            box-sizing: border-box;
        }

        .diary-inline-actions {
            display: flex;
            gap: 8px;
            justify-content: flex-end;
        }

        .btn-inline-save {
            background: linear-gradient(135deg, #10B981 0%, #059669 100%);
            border: none;
            color: #FFF;
            border-radius: 6px;
            padding: 4px 12px;
            font-size: 11.5px;
            font-weight: 700;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 4px;
        }

        .btn-inline-cancel {
            background: var(--bg-input);
            border: 1px solid var(--border-card);
            color: var(--text-secondary);
            border-radius: 6px;
            padding: 4px 10px;
            font-size: 11.5px;
            font-weight: 600;
            cursor: pointer;
        }

        @media (max-width: 768px) {
            .diary-toolbar {
                padding: 16px 14px !important;
                border-radius: 16px !important;
            }
            .diary-filters {
                flex-direction: column !important;
                align-items: stretch !important;
            }
            .diary-count-pill {
                margin-left: 0 !important;
                text-align: center !important;
            }
        }

        /* Students Section Styles */
        .students-toolbar {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 20px;
            padding: 20px 24px;
            margin-bottom: 20px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            box-shadow: var(--glass-shadow, var(--shadow-card));
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 15px;
        }

        .students-toolbar-title h3 {
            color: var(--text-primary);
            font-size: 18px;
            margin: 0;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .students-toolbar-title p {
            color: var(--text-secondary);
            font-size: 13px;
            margin: 4px 0 0 0;
        }

        .students-toolbar-actions {
            display: flex;
            align-items: center;
            gap: 10px;
            flex-wrap: wrap;
        }

        .btn-student-action {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            font-family: 'Plus Jakarta Sans', sans-serif;
            border-radius: 12px;
            cursor: pointer;
            transition: all 0.25s ease;
        }

        .btn-add-student {
            background: var(--btn-bg);
            border: none;
            color: var(--btn-text);
            font-weight: 700;
            font-size: 13px;
            padding: 9px 18px;
            box-shadow: var(--shadow-primary);
        }

        .btn-add-student:hover {
            transform: translateY(-2px);
            box-shadow: var(--shadow-primary);
            filter: brightness(1.1);
        }

        .btn-trash-student {
            background: rgba(239, 68, 68, 0.1);
            border: 1px dashed rgba(239, 68, 68, 0.5);
            color: #EF4444;
            padding: 9px 14px;
            font-size: 14px;
        }

        .btn-trash-student:hover {
            background: rgba(239, 68, 68, 0.2);
            border-color: #EF4444;
            transform: translateY(-2px);
        }

        /* Students Cards Grid */
        .students-cards-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 18px;
            margin-bottom: 24px;
        }

        @media (max-width: 1024px) {
            .students-cards-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }

        @media (max-width: 768px) {
            .students-toolbar {
                padding: 16px 14px !important;
                border-radius: 16px !important;
                flex-direction: column !important;
                align-items: stretch !important;
            }
            .students-toolbar-actions {
                justify-content: flex-start;
            }
            .students-cards-grid {
                grid-template-columns: 1fr;
            }
        }

        .student-profile-card {
            background: var(--glass-bg, var(--bg-card));
            border: 1.5px solid rgba(var(--color-primary-rgb), 0.32);
            border-radius: 20px;
            padding: 18px 20px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            gap: 14px;
            cursor: pointer;
            position: relative;
            transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            backdrop-filter: blur(var(--glass-blur, 18px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 18px));
            box-shadow: 0 4px 16px rgba(0, 0, 0, 0.04), 0 2px 6px rgba(var(--color-primary-rgb), 0.08);
        }

        .student-profile-card:hover {
            border-color: var(--color-primary);
            transform: translateY(-3px);
            box-shadow: var(--shadow-primary);
        }

        .student-profile-card.active {
            border-color: var(--color-primary);
            box-shadow: 0 0 0 2.5px rgba(var(--color-primary-rgb), 0.35), var(--shadow-card);
            background: var(--bg-card-alt);
        }

        .student-profile-card.active::after {
            content: 'Đang xem';
            position: absolute;
            top: 10px;
            right: 12px;
            background: var(--nav-active-bg);
            border: 1px solid var(--color-primary);
            color: var(--color-primary);
            font-size: 10.5px;
            font-weight: 700;
            padding: 2px 8px;
            border-radius: 10px;
        }

        .student-card-header {
            display: flex;
            align-items: center;
            gap: 12px;
        }

        .student-initial-avatar {
            width: 44px;
            height: 44px;
            border-radius: 50%;
            font-size: 17px;
            font-weight: 800;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
            box-shadow: 0 2px 8px rgba(var(--color-primary-rgb), 0.2);
            background: var(--nav-active-bg);
            border: 2px solid var(--color-primary);
            color: var(--color-primary);
        }

        .student-card-info {
            flex: 1;
            min-width: 0;
        }

        .student-card-name {
            font-size: 15.5px;
            font-weight: 700;
            color: var(--text-primary);
            line-height: 1.25;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .student-card-sub {
            font-size: 12px;
            color: var(--text-secondary);
            margin-top: 3px;
            display: flex;
            align-items: center;
            gap: 6px;
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .student-card-schedule {
            background: rgba(var(--color-primary-rgb), 0.05);
            border: 1px solid rgba(var(--color-primary-rgb), 0.2);
            border-radius: 12px;
            padding: 7px 12px;
            font-size: 12px;
            color: var(--text-primary);
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .student-card-schedule i {
            color: var(--color-primary);
            font-size: 12px;
            flex-shrink: 0;
        }

        .student-card-schedule span {
            white-space: nowrap;
            overflow: hidden;
            text-overflow: ellipsis;
        }

        .student-card-metrics {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 8px;
            text-align: center;
        }

        .card-metric-box {
            background: rgba(var(--color-primary-rgb), 0.04);
            border: 1px solid rgba(var(--color-primary-rgb), 0.18);
            border-radius: 12px;
            padding: 6px 3px;
        }

        .card-metric-val {
            font-size: 14.5px;
            font-weight: 800;
            line-height: 1.2;
            color: var(--text-primary);
        }

        .card-metric-lbl {
            font-size: 10px;
            font-weight: 600;
            color: var(--text-secondary);
            margin-top: 2px;
        }

        .student-card-actions {
            display: flex;
            gap: 8px;
            align-items: center;
            margin-top: 2px;
        }

        .btn-card-detail {
            flex: 1;
            background: var(--nav-active-bg);
            border: 1px solid rgba(var(--color-primary-rgb), 0.35);
            color: var(--color-primary);
            font-size: 12px;
            font-weight: 700;
            padding: 8px 12px;
            border-radius: 10px;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
            transition: all 0.2s ease;
        }

        .btn-card-detail:hover {
            background: var(--btn-bg);
            color: var(--btn-text);
            border-color: var(--color-primary);
        }

        .btn-card-diary {
            background: var(--bg-card);
            border: 1px solid rgba(var(--color-primary-rgb), 0.25);
            color: var(--text-primary);
            font-size: 12px;
            font-weight: 600;
            padding: 8px 14px;
            border-radius: 10px;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
            transition: all 0.2s ease;
        }

        .btn-card-diary:hover {
            background: var(--nav-hover-bg);
            border-color: var(--color-primary);
        }

        /* Schedule Day Pills for Add/Edit Student */
        .schedule-day-pills {
            display: flex;
            gap: 6px;
            width: 100%;
        }
        .day-pill {
            flex: 1;
            padding: 8px 0;
            text-align: center;
            border-radius: 8px;
            background: var(--bg-input);
            border: 1px solid var(--border-color);
            color: var(--text-secondary);
            font-size: 12.5px;
            font-weight: 700;
            cursor: pointer;
            transition: all 0.2s ease;
            user-select: none;
        }
        .day-pill:hover {
            background: var(--nav-hover-bg);
            border-color: var(--color-primary);
            color: var(--text-primary);
        }
        .day-pill.active {
            background: var(--btn-bg);
            border-color: var(--color-primary);
            color: var(--btn-text);
            box-shadow: var(--shadow-primary);
        }

        /* Tuition Section Styles */
        .tuition-toolbar {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 20px;
            padding: 20px 24px;
            margin-bottom: 20px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            box-shadow: var(--glass-shadow, var(--shadow-card));
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 15px;
        }

        .tuition-toolbar-title h3 {
            color: var(--text-heading, var(--text-primary)) !important;
            font-size: 18px;
            margin: 0;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .tuition-toolbar-title p {
            color: var(--text-secondary);
            font-size: 13px;
            margin: 4px 0 0 0;
        }

        .tuition-filters {
            display: flex;
            align-items: center;
            gap: 12px;
            flex-wrap: wrap;
        }

        .tuition-filter-item {
            display: flex;
            align-items: center;
            gap: 8px;
            background: var(--bg-input);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 8px 14px;
        }

        .tuition-filter-item label {
            font-size: 12.5px;
            font-weight: 600;
            color: var(--text-secondary);
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .tuition-filter-item select {
            background: transparent;
            border: none;
            color: var(--text-heading);
            font-weight: 700;
            font-size: 13.5px;
            outline: none;
            cursor: pointer;
        }

        .tuition-filter-item select option {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        /* Toolbars stacking contexts: luôn nằm trên các widget/bảng phía dưới */
        .report-filter-toolbar,
        .diary-toolbar,
        .tuition-toolbar {
            position: relative !important;
            z-index: 50 !important;
        }
        .report-filter-toolbar.has-open-dropdown,
        .diary-toolbar.has-open-dropdown,
        .tuition-toolbar.has-open-dropdown,
        .report-filter-toolbar:has(.custom-dropdown-wrap.open),
        .diary-toolbar:has(.custom-dropdown-wrap.open),
        .tuition-toolbar:has(.custom-dropdown-wrap.open) {
            z-index: 1050 !important;
        }

        /* Các khối phía sau toolbars giữ z-index thấp để không bao giờ che đè menu dropdown */
        #tutorQuickAnnouncementWidget,
        .tutor-diary-card,
        .tuition-banner-grid,
        .tuition-banner-card,
        .tuition-table-card,
        .report-preview-wrapper {
            position: relative;
            z-index: 1;
        }

        /* Custom Filter Dropdown System (Thay thế select native bằng menu sang trọng) */
        .custom-dropdown-wrap {
            position: relative !important;
            cursor: pointer;
            user-select: none;
            transition: all 0.2s cubic-bezier(0.16, 1, 0.3, 1);
        }
        .custom-dropdown-wrap:hover {
            border-color: var(--color-primary) !important;
            box-shadow: 0 2px 10px rgba(142, 77, 255, 0.12);
        }
        .custom-dropdown-wrap.open {
            border-color: var(--color-primary) !important;
            box-shadow: 0 0 0 3px rgba(142, 77, 255, 0.16) !important;
            z-index: 1060 !important;
        }
        .custom-dropdown-value-group {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            cursor: pointer;
        }
        .custom-dropdown-selected {
            font-size: 13.5px;
            font-weight: 700;
            color: var(--color-primary, #8E4DFF);
            white-space: nowrap;
        }
        .custom-dropdown-icon {
            font-size: 11px;
            color: var(--color-primary, #8E4DFF);
            margin-left: 2px;
            transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
        }
        .custom-dropdown-wrap.open .custom-dropdown-icon {
            transform: rotate(180deg);
        }
        .custom-dropdown-wrap select {
            display: none !important;
        }

        /* Floating Menu Popup: Nền đặc 100% không trong suốt, z-index cao tuyệt đối */
        .custom-dropdown-menu {
            display: none;
            position: absolute;
            top: calc(100% + 8px);
            right: 0;
            min-width: 210px;
            width: max-content;
            max-width: calc(100vw - 32px);
            background: #FFFFFF !important;
            border: 1px solid var(--border-card, var(--border-color, #E2E8F0)) !important;
            border-radius: 14px !important;
            box-shadow: 0 16px 40px rgba(0, 0, 0, 0.20), 0 4px 12px rgba(0, 0, 0, 0.08) !important;
            padding: 6px !important;
            z-index: 9999 !important;
            max-height: 280px;
            overflow-y: auto;
            backdrop-filter: none !important;
            -webkit-backdrop-filter: none !important;
            opacity: 1 !important;
        }
        .report-control-group .custom-dropdown-menu {
            left: 0 !important;
            right: auto !important;
        }
        .custom-dropdown-menu.open {
            display: block !important;
            animation: customDropdownFadeIn 0.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
        }
        @keyframes customDropdownFadeIn {
            from {
                opacity: 0;
                transform: translateY(-6px) scale(0.98);
            }
            to {
                opacity: 1;
                transform: translateY(0) scale(1);
            }
        }
        .custom-dropdown-menu::-webkit-scrollbar {
            width: 5px;
        }
        .custom-dropdown-menu::-webkit-scrollbar-track {
            background: transparent;
        }
        .custom-dropdown-menu::-webkit-scrollbar-thumb {
            background: var(--border-color, #CBD5E1);
            border-radius: 10px;
        }
        .custom-dropdown-menu::-webkit-scrollbar-thumb:hover {
            background: var(--color-primary);
        }
        .custom-dropdown-item {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 9px 12px;
            border-radius: 9px;
            font-size: 13.5px;
            font-weight: 500;
            color: #1E293B !important;
            background: transparent;
            cursor: pointer;
            transition: all 0.15s ease;
            margin-bottom: 2px;
            user-select: none;
        }
        .custom-dropdown-item:last-child {
            margin-bottom: 0;
        }
        .custom-dropdown-item:hover {
            background: var(--nav-hover-bg, rgba(142, 77, 255, 0.08)) !important;
            color: var(--color-primary) !important;
            transform: translateX(2px);
        }
        .custom-dropdown-item.active {
            background: var(--nav-active-bg, rgba(142, 77, 255, 0.14)) !important;
            color: var(--color-primary) !important;
            font-weight: 700;
        }
        .custom-dropdown-item .item-check {
            font-size: 11px;
            color: var(--color-primary);
            opacity: 0;
            transition: opacity 0.15s ease;
        }
        .custom-dropdown-item.active .item-check {
            opacity: 1;
        }

        /* Dark Theme overrides cho Custom Dropdown Menu */
        [data-theme="dark"] .custom-dropdown-menu,
        [data-dark-mode="true"] .custom-dropdown-menu,
        body.theme-dark-purple .custom-dropdown-menu,
        body.theme-dreamy-cosmic-full .custom-dropdown-menu,
        body.theme-neon-seoul-full .custom-dropdown-menu,
        body.theme-mystic-blue-full .custom-dropdown-menu,
        body.theme-blossom-noir-full .custom-dropdown-menu,
        body.theme-violet-planet-full .custom-dropdown-menu,
        html[data-theme="dark"] .custom-dropdown-menu {
            background: #182234 !important;
            border-color: #334155 !important;
            box-shadow: 0 16px 40px rgba(0, 0, 0, 0.55), 0 4px 12px rgba(0, 0, 0, 0.3) !important;
        }
        [data-theme="dark"] .custom-dropdown-item,
        [data-dark-mode="true"] .custom-dropdown-item,
        body.theme-dark-purple .custom-dropdown-item,
        body.theme-dreamy-cosmic-full .custom-dropdown-item,
        body.theme-neon-seoul-full .custom-dropdown-item,
        body.theme-mystic-blue-full .custom-dropdown-item,
        body.theme-blossom-noir-full .custom-dropdown-item,
        body.theme-violet-planet-full .custom-dropdown-item,
        html[data-theme="dark"] .custom-dropdown-item {
            color: #F8FAFC !important;
        }
        [data-theme="dark"] .custom-dropdown-item:hover,
        [data-dark-mode="true"] .custom-dropdown-item:hover,
        body.theme-dark-purple .custom-dropdown-item:hover,
        body.theme-dreamy-cosmic-full .custom-dropdown-item:hover,
        body.theme-neon-seoul-full .custom-dropdown-item:hover,
        body.theme-mystic-blue-full .custom-dropdown-item:hover,
        body.theme-blossom-noir-full .custom-dropdown-item:hover,
        body.theme-violet-planet-full .custom-dropdown-item:hover,
        html[data-theme="dark"] .custom-dropdown-item:hover {
            background: rgba(255, 255, 255, 0.08) !important;
        }

        /* Tuition Banner Grid */
        .tuition-banner-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 16px;
            margin-bottom: 24px;
        }

        @media (max-width: 768px) {
            .tuition-toolbar {
                padding: 16px 14px !important;
                border-radius: 16px !important;
                flex-direction: column !important;
                align-items: stretch !important;
            }
            .tuition-banner-grid {
                grid-template-columns: 1fr;
            }
        }

        .tuition-banner-card {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 16px;
            padding: 18px 20px;
            display: flex;
            flex-direction: column;
            gap: 8px;
            backdrop-filter: blur(var(--glass-blur, 18px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 18px));
            transition: all 0.25s ease;
            box-shadow: var(--glass-shadow, var(--shadow-card));
        }

        .tuition-banner-card:hover {
            transform: translateY(-2px);
            box-shadow: var(--shadow-primary);
            border-color: var(--color-primary);
        }

        .tuition-banner-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .tuition-banner-lbl {
            font-size: 12.5px;
            font-weight: 600;
            color: var(--text-secondary);
        }

        .tuition-banner-icon {
            width: 36px;
            height: 36px;
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 15px;
        }

        .tuition-banner-val {
            font-size: 22px;
            font-weight: 800;
            line-height: 1.2;
            font-family: 'Space Grotesk', 'Plus Jakarta Sans', sans-serif;
            letter-spacing: -0.3px;
            color: var(--text-heading, var(--text-primary));
        }

        .tuition-banner-sub {
            font-size: 11.5px;
            color: var(--text-muted);
            display: flex;
            align-items: center;
            gap: 4px;
        }

        /* Tuition Status Badges */
        .tuition-status-badge {
            border: none;
            padding: 6px 14px;
            border-radius: 20px;
            font-size: 11.5px;
            font-weight: 700;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            transition: all 0.2s ease;
            outline: none;
        }

        .tuition-status-badge.status-paid {
            background: rgba(16, 185, 129, 0.15);
            border: 1px solid #10B981;
            color: var(--text-primary);
        }

        .tuition-status-badge.status-paid i {
            color: #059669;
        }

        .tuition-status-badge.status-paid:hover {
            background: rgba(16, 185, 129, 0.28);
            transform: scale(1.03);
        }

        .tuition-status-badge.status-unpaid {
            background: rgba(239, 68, 68, 0.15);
            border: 1px solid #EF4444;
            color: var(--text-primary);
        }

        .tuition-status-badge.status-unpaid i {
            color: #DC2626;
        }

        .tuition-status-badge.status-unpaid:hover {
            background: rgba(239, 68, 68, 0.28);
            transform: scale(1.03);
        }

        .btn-tuition-invoice {
            background: var(--nav-active-bg);
            border: 1px solid var(--border-color);
            color: var(--text-heading);
            font-size: 12px;
            font-weight: 700;
            padding: 6px 14px;
            border-radius: 8px;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            transition: all 0.2s ease;
        }

        .btn-tuition-invoice:hover {
            background: var(--btn-bg);
            color: var(--btn-text);
            transform: translateY(-1px);
        }

        /* Report Section Styles */
        .report-filter-toolbar {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 20px;
            padding: 20px 24px;
            margin-bottom: 22px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            box-shadow: var(--glass-shadow, var(--shadow-card));
        }

        .report-toolbar-header {
            margin-bottom: 16px;
        }

        .report-toolbar-header h3 {
            color: var(--text-primary);
            font-size: 18px;
            margin: 0;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .report-toolbar-header p {
            color: var(--text-secondary);
            font-size: 13px;
            margin: 4px 0 0 0;
        }

        .report-filter-controls {
            display: flex;
            align-items: flex-end;
            gap: 14px;
            flex-wrap: wrap;
        }

        .report-control-group {
            display: flex;
            flex-direction: column;
            gap: 6px;
        }

        .report-control-label {
            font-size: 12px;
            font-weight: 700;
            color: var(--text-secondary);
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .report-input-box {
            background: var(--bg-input);
            border: 1px solid var(--border-color);
            border-radius: 10px;
            padding: 8px 12px;
            color: var(--text-primary);
            font-size: 13px;
            font-family: inherit;
            outline: none;
            transition: all 0.2s ease;
        }

        .report-input-box:focus {
            border-color: var(--color-primary);
            background: var(--nav-hover-bg);
        }

        .report-date-input {
            color-scheme: dark;
            min-width: 140px;
        }

        /* Vietnamese Date Picker Container & Controls (DD/MM/YYYY) */
        .vn-date-picker-box {
            position: relative;
            display: inline-flex;
            align-items: center;
            width: 100%;
            min-width: 140px;
        }

        .vn-date-picker-box .vn-date-input {
            width: 100%;
            padding-right: 36px !important;
            font-variant-numeric: tabular-nums;
            letter-spacing: 0.3px;
            box-sizing: border-box;
        }

        .vn-date-picker-box .vn-date-picker-icon-btn {
            position: absolute;
            right: 8px;
            top: 50%;
            transform: translateY(-50%);
            background: transparent;
            border: none;
            color: var(--text-secondary);
            font-size: 13.5px;
            padding: 4px;
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 1;
            pointer-events: none;
            transition: color 0.2s ease;
        }

        .vn-date-picker-box:hover .vn-date-picker-icon-btn {
            color: var(--color-primary);
        }

        .vn-date-picker-box .vn-hidden-native-picker {
            position: absolute;
            right: 2px;
            top: 50%;
            transform: translateY(-50%);
            width: 34px;
            height: 34px;
            opacity: 0;
            cursor: pointer;
            z-index: 2;
            padding: 0;
            margin: 0;
            border: none;
            background: transparent;
            color-scheme: dark;
        }

        .report-select {
            min-width: 160px;
            cursor: pointer;
        }

        .report-select option {
            background: var(--bg-card);
            color: var(--text-primary);
        }

        .report-actions {
            display: flex;
            align-items: center;
            gap: 10px;
            margin-left: auto;
            flex-wrap: wrap;
        }

        .btn-report-preview {
            background: var(--btn-bg);
            border: none;
            color: var(--btn-text);
            font-weight: 700;
            font-size: 13px;
            padding: 9px 20px;
            border-radius: 10px;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 7px;
            box-shadow: var(--shadow-primary);
            transition: all 0.2s ease;
        }

        .btn-report-preview:hover {
            transform: translateY(-1px);
            box-shadow: var(--shadow-primary);
        }

        .btn-report-export {
            background: linear-gradient(135deg, #10B981 0%, #059669 100%);
            border: none;
            color: #FFF;
            font-weight: 700;
            font-size: 13px;
            padding: 9px 20px;
            border-radius: 10px;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 7px;
            box-shadow: 0 4px 15px rgba(16, 185, 129, 0.25);
            transition: all 0.2s ease;
        }

        .btn-report-export:hover {
            transform: translateY(-1px);
            box-shadow: 0 6px 20px rgba(16, 185, 129, 0.45);
        }

        .btn-report-export:disabled {
            opacity: 0.6;
            cursor: not-allowed;
            transform: none !important;
        }

        .btn-report-pdf {
            background: linear-gradient(135deg, #EF4444 0%, #DC2626 100%);
            border: none;
            color: #FFF;
            font-weight: 700;
            font-size: 13px;
            padding: 9px 20px;
            border-radius: 10px;
            cursor: pointer;
            display: inline-flex;
            align-items: center;
            gap: 7px;
            box-shadow: 0 4px 15px rgba(239, 68, 68, 0.25);
            transition: all 0.2s ease;
        }

        .btn-report-pdf:hover {
            transform: translateY(-1px);
            box-shadow: 0 6px 20px rgba(239, 68, 68, 0.45);
        }

        .btn-report-pdf:disabled {
            opacity: 0.6;
            cursor: not-allowed;
            transform: none !important;
        }

        @media (max-width: 768px) {
            .report-filter-card {
                padding: 16px 14px !important;
                border-radius: 16px !important;
            }
            .report-filter-controls {
                flex-direction: column !important;
                align-items: stretch !important;
            }
            .report-actions {
                margin-left: 0 !important;
                margin-top: 8px;
                width: 100%;
            }
            .btn-report-preview,
            .btn-report-export,
            .btn-report-pdf {
                flex: 1;
                justify-content: center;
            }
            .report-capture-card {
                padding: 18px 15px !important;
            }
            .report-stats-grid {
                grid-template-columns: 1fr !important;
            }
            .report-card-banner {
                flex-direction: column !important;
                align-items: flex-start !important;
            }
        }

        /* Report Capture Card for html2canvas */
        .report-preview-wrapper {
            margin-top: 15px;
            display: flex;
            flex-direction: column;
            align-items: center;
        }

        .report-capture-card {
            width: 100%;
            max-width: 820px;
            background: var(--bg-card);
            border: 2px solid var(--border-color);
            border-radius: 24px;
            padding: 30px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.6);
            position: relative;
            box-sizing: border-box;
            color: var(--text-primary);
        }

        .report-card-banner {
            border-bottom: 2px solid var(--border-color);
            padding-bottom: 20px;
            margin-bottom: 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 15px;
        }

        .report-brand-title {
            font-size: 20px;
            font-weight: 900;
            color: var(--text-primary);
            letter-spacing: 0.3px;
        }

        .report-brand-sub {
            font-size: 12.5px;
            color: var(--text-secondary);
            margin-top: 4px;
        }

        .report-meta-pills {
            display: flex;
            gap: 8px;
            flex-wrap: wrap;
        }

        .report-meta-pill {
            background: var(--nav-active-bg);
            border: 1px solid var(--border-color);
            color: var(--text-heading);
            font-size: 11.5px;
            font-weight: 700;
            padding: 5px 12px;
            border-radius: 20px;
            display: inline-flex;
            align-items: center;
            gap: 6px;
        }

        .report-stats-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 12px;
            margin-bottom: 24px;
        }

        .report-stat-box {
            background: var(--bg-card-alt);
            border: 1px solid var(--border-card);
            border-radius: 14px;
            padding: 12px 14px;
            text-align: center;
        }

        .report-stat-num {
            font-size: 18px;
            font-weight: 800;
            color: var(--text-primary);
        }

        .report-stat-lbl {
            font-size: 11px;
            color: var(--text-secondary);
            font-weight: 600;
            margin-top: 3px;
        }

        .report-sessions-list {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .report-session-item {
            background: var(--bg-card-alt);
            border: 1px solid var(--border-card);
            border-radius: 14px;
            padding: 14px 16px;
            transition: all 0.2s ease;
        }

        .report-session-top {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 8px;
            flex-wrap: wrap;
            gap: 6px;
        }

        .report-session-date {
            font-size: 13.5px;
            font-weight: 700;
            color: var(--text-primary);
            display: flex;
            align-items: center;
            gap: 6px;
        }

        .report-session-topic {
            font-size: 13.5px;
            color: var(--color-primary);
            font-weight: 600;
            margin-bottom: 6px;
        }

        .report-session-comment {
            font-size: 12.5px;
            color: var(--text-primary);
            line-height: 1.45;
            background: var(--bg-card-alt);
            border-left: 3px solid var(--color-primary);
            padding: 8px 12px;
            border-radius: 0 8px 8px 0;
            margin-top: 6px;
        }

        .report-card-footer {
            margin-top: 24px;
            padding-top: 16px;
            border-top: 1px dashed var(--border-color);
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 11.5px;
            color: var(--text-muted);
            flex-wrap: wrap;
            gap: 10px;
        }

        /* Schedule Table */
        .schedule-section {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-card));
            border-radius: 20px;
            padding: 25px;
            margin-bottom: 25px;
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            overflow-x: auto;
        }
        .schedule-section h3 { color: var(--color-primary); margin-bottom: 15px; font-size: 18px; }
        
        /* Student Buttons */
        .student-buttons-container {
            display: flex;
            gap: 15px;
            flex-wrap: wrap;
            margin-bottom: 25px;
            justify-content: center;
        }
        .student-btn {
            background: var(--bg-input);
            border: 1px solid var(--border-card);
            color: var(--text-primary);
            padding: 12px 24px;
            border-radius: 30px;
            font-size: 15px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            box-shadow: 0 5px 15px rgba(0,0,0,0.2);
        }
        .student-btn:hover { background: var(--nav-hover-bg); border-color: var(--color-primary); transform: translateY(-3px); }
        .student-btn.active { background: var(--btn-bg); border-color: var(--color-primary); box-shadow: var(--shadow-primary); }
        
        /* Tutor Student Detail Area */
        #tutorStudentDetail { display: none; position: relative; z-index: 50; }
        #adminDashboardBox { position: relative; z-index: 50; }
        
        /* ================= INVOICE STYLES (APPROVED E-RECEIPT) ================= */
        .invoice-container {
            width: 100%;
            max-width: 500px;
            margin: 0 auto;
            background: #FFFFFF;
            color: #0F172A;
            border-radius: 28px;
            padding: 26px 24px 26px 24px;
            box-shadow: 0 35px 80px -15px rgba(0, 0, 0, 0.6), 0 0 0 1px rgba(0, 0, 0, 0.04);
            position: relative;
            overflow: hidden;
            box-sizing: border-box;
            font-family: 'Plus Jakarta Sans', -apple-system, sans-serif;
        }

        .invoice-container::before {
            content: '';
            position: absolute;
            top: 0; left: 0; right: 0;
            height: 6px;
            background: linear-gradient(90deg, #8E4DFF 0%, #3B82F6 50%, #10B981 100%);
        }

        .inv-head {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding-bottom: 16px;
            border-bottom: 1px dashed #E2E8F0;
        }
        .inv-head-left {
            display: flex;
            align-items: center;
            gap: 12px;
        }
        .inv-avatar {
            width: 48px;
            height: 48px;
            border-radius: 15px;
            background: linear-gradient(135deg, #7C3AED 0%, #5B21B6 100%);
            color: #FFFFFF;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            box-shadow: 0 4px 12px rgba(124, 58, 237, 0.25);
        }
        .inv-user-meta .inv-tag-mini {
            font-size: 10.5px;
            font-weight: 800;
            letter-spacing: 0.8px;
            text-transform: uppercase;
            color: #64748B;
            display: block;
            margin-bottom: 2px;
        }
        .inv-user-meta h2 {
            font-size: 21px;
            font-weight: 800;
            color: #0F172A;
            letter-spacing: -0.4px;
            line-height: 1.2;
            margin: 0;
        }
        .inv-head-right {
            text-align: right;
        }
        .inv-pill-status {
            display: inline-flex;
            align-items: center;
            gap: 6px;
            background: #F3E8FF;
            color: #6D28D9;
            font-size: 11.5px;
            font-weight: 800;
            padding: 6px 14px;
            border-radius: 20px;
            letter-spacing: 0.3px;
            border: 1px solid rgba(109, 40, 217, 0.12);
        }

        .inv-section-title {
            font-size: 10.5px;
            font-weight: 800;
            letter-spacing: 0.6px;
            text-transform: uppercase;
            color: #64748B;
            margin: 14px 0 8px 0;
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .inv-section-title i { color: #7C3AED; }

        .metrics-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 10px;
            align-items: stretch;
        }
        .metric-card {
            background: #F8FAFC;
            border: 1px solid #E2E8F0;
            border-radius: 16px;
            padding: 12px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            height: 100%;
            box-sizing: border-box;
        }
        .metric-card-header {
            display: flex;
            align-items: center;
            justify-content: space-between;
            font-size: 11px;
            font-weight: 700;
            color: #334155;
            margin-bottom: 8px;
        }
        .metric-card-header i { font-size: 13px; }

        .metric-badges {
            display: flex;
            gap: 6px;
            margin-bottom: 8px;
        }
        .m-badge {
            flex: 1;
            background: #FFFFFF;
            border: 1px solid #E2E8F0;
            border-radius: 10px;
            padding: 5px 2px;
            text-align: center;
            box-shadow: 0 1px 2px rgba(0,0,0,0.02);
        }
        .m-num {
            font-size: 17px;
            font-weight: 800;
            line-height: 1.1;
            color: #0F172A;
        }
        .m-lbl {
            font-size: 9.5px;
            font-weight: 600;
            color: #64748B;
            margin-top: 2px;
        }

        .metric-notes {
            margin-top: auto;
            font-size: 10px;
            background: #FFFFFF;
            border: 1px solid #E2E8F0;
            border-radius: 8px;
            padding: 7px 8px;
            line-height: 1.35;
            color: #475569;
            min-height: 48px;
            display: flex;
            align-items: center;
            box-sizing: border-box;
        }
        .metric-notes span { font-weight: 700; color: #1E293B; }
        .tuition-receipt-card .text-green { color: #059669 !important; }
        .tuition-receipt-card .text-amber { color: #D97706 !important; }
        .tuition-receipt-card .text-red { color: #DC2626 !important; }
        .tuition-receipt-card .text-purple { color: #7C3AED !important; }

        .fee-card {
            background: linear-gradient(135deg, #FAF5FF 0%, #F5F3FF 100%);
            border: 1px solid #E9D5FF;
            border-radius: 16px;
            padding: 14px 16px;
            margin-top: 12px;
        }
        .fee-row {
            display: flex;
            justify-content: space-between;
            align-items: center;
            font-size: 12px;
            color: #4B5563;
            margin-bottom: 6px;
            font-weight: 500;
        }
        .fee-row b { color: #1F2937; }
        .fee-row.grand-total {
            margin-top: 8px;
            padding-top: 8px;
            border-top: 1px dashed #D8B4FE;
            margin-bottom: 0;
            color: #0F172A;
        }
        .fee-row.grand-total .total-label {
            font-size: 12.5px;
            font-weight: 800;
            letter-spacing: 0.3px;
            text-transform: uppercase;
            color: #4C1D95;
        }
        .fee-row.grand-total .total-val {
            font-size: 22px;
            font-weight: 900;
            color: #6D28D9;
            letter-spacing: -0.5px;
            font-family: 'Space Grotesk', 'Plus Jakarta Sans', sans-serif;
        }

        .bottom-action-container {
            display: grid;
            grid-template-columns: 1fr 190px;
            gap: 12px;
            margin-top: 12px;
            align-items: stretch;
        }
        .msg-box {
            background: #F8FAFC;
            border: 1px solid #E2E8F0;
            border-radius: 18px;
            padding: 14px;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }
        .msg-header {
            font-size: 11.5px;
            font-weight: 700;
            color: #64748B;
            display: flex;
            align-items: center;
            gap: 6px;
            margin-bottom: 8px;
        }
        .msg-header i { color: #7C3AED; }
        .msg-text {
            font-size: 11.5px;
            color: #334155;
            line-height: 1.55;
            font-weight: 500;
            outline: none;
        }
        .msg-footer {
            font-size: 10px;
            color: #94A3B8;
            margin-top: 8px;
            font-style: italic;
        }
        .btn-draft-saved {
            background: #F5F3FF !important;
            border-color: #DDD6FE !important;
            color: #6D28D9 !important;
            font-weight: 700 !important;
        }
        .btn-draft-saved:hover {
            background: #EDE9FE !important;
            border-color: #C4B5FD !important;
        }

        .qr-card {
            background: #FFFFFF;
            border: 1.5px solid #E9D5FF;
            border-radius: 18px;
            padding: 10px 8px 8px 8px;
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            text-align: center;
            box-shadow: 0 4px 15px rgba(124, 58, 237, 0.06);
            background: linear-gradient(180deg, #FFFFFF 0%, #FAF5FF 100%);
        }
        .qr-img {
            width: 168px;
            height: 168px;
            object-fit: contain;
            border-radius: 12px;
            background: #FFFFFF;
            padding: 4px;
            border: 1px solid #E2E8F0;
            box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
        }
        .qr-label {
            font-size: 11px;
            font-weight: 800;
            color: #6D28D9;
            margin-top: 6px;
            display: flex;
            align-items: center;
            gap: 5px;
            letter-spacing: 0.3px;
        }

        .pin-input-container { display: none; margin-top: 15px; }
        .pin-input-container input { width: 100%; background: var(--bg-input); border: 1px solid var(--border-color); border-radius: 12px; padding: 14px 15px; color: var(--text-primary); font-size: 15px; outline: none; font-family: 'Inter', sans-serif; text-align: center; letter-spacing: 5px; text-indent: 5px; font-weight: bold;}
        .pin-input-container input:focus { border-color: var(--color-primary); box-shadow: var(--shadow-primary); }
        .export-btn-container { text-align: center; margin-top: 20px; }
        .btn-export { background: linear-gradient(135deg, #10B981 0%, #059669 100%); color: #FFF; border: none; padding: 12px 30px; border-radius: 30px; font-weight: 700; font-size: 15px; cursor: pointer; transition: 0.3s; box-shadow: 0 6px 20px rgba(16, 185, 129, 0.4); display: inline-flex; align-items: center; gap: 8px;}
        .btn-export:hover { transform: translateY(-2px); box-shadow: 0 10px 25px rgba(16, 185, 129, 0.6); }
        .btn-show-more {
            background: var(--nav-active-bg);
            border: 1px solid var(--border-color);
            color: var(--text-heading);
            padding: 8px 24px;
            border-radius: 20px;
            font-size: 13px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
        }
        .btn-show-more:hover {
            background: var(--color-primary);
            color: var(--btn-text);
            border-color: var(--color-primary);
            box-shadow: var(--shadow-primary);
            transform: translateY(-1px);
        }
        /* MODALS FOR TUTOR ACTIONS */
        .modal-overlay {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: var(--bg-overlay);
            backdrop-filter: blur(8px);
            z-index: 2000;
            display: none;
            align-items: center;
            justify-content: center;
            padding: 20px;
            box-sizing: border-box;
        }
        .modal-content {
            background: var(--glass-bg, var(--bg-card));
            border: 1px solid var(--glass-border, var(--border-color));
            box-shadow: var(--glass-shadow, var(--shadow-card));
            backdrop-filter: blur(var(--glass-blur, 20px));
            -webkit-backdrop-filter: blur(var(--glass-blur, 20px));
            border-radius: 20px;
            width: 100%;
            max-width: 500px;
            padding: 30px;
            color: var(--text-primary);
            position: relative;
            max-height: 90vh;
            overflow-y: auto;
            box-sizing: border-box;
        }

        @media (max-width: 480px) {
            .modal-overlay {
                padding: 12px 10px;
            }
            .modal-content {
                padding: 20px 16px !important;
                border-radius: 16px !important;
            }
            .invoice-container {
                padding: 18px 14px !important;
                border-radius: 20px !important;
            }
            .metrics-grid {
                grid-template-columns: 1fr !important;
                gap: 8px !important;
            }
            .bottom-action-container {
                grid-template-columns: 1fr !important;
                gap: 12px !important;
            }
            .qr-card {
                padding: 12px !important;
            }
            .qr-img {
                width: 140px !important;
                height: 140px !important;
            }
        }
        .modal-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 20px;
            border-bottom: 1px solid var(--border-card);
            padding-bottom: 10px;
        }
        .modal-header h3 {
            margin: 0;
            color: var(--text-heading);
            font-size: 20px;
        }
        .modal-close {
            background: none;
            border: none;
            color: var(--text-secondary);
            font-size: 20px;
            cursor: pointer;
        }
        .modal-form-group {
            margin-bottom: 15px;
            text-align: left;
        }
        .modal-form-group label {
            display: block;
            font-size: 12px;
            color: var(--text-secondary);
            margin-bottom: 6px;
            text-transform: uppercase;
            font-weight: 700;
            letter-spacing: 0.5px;
        }
        .modal-form-group input, .modal-form-group select, .modal-form-group textarea {
            width: 100%;
            padding: 10px 14px;
            border-radius: 10px;
            border: 1px solid var(--border-color);
            background: var(--bg-input);
            color: var(--text-primary);
            outline: none;
            font-family: Inter, -apple-system, BlinkMacSystemFont, sans-serif;
            font-size: 14px;
            line-height: 1.5;
            box-sizing: border-box;
        }
        .modal-form-group input:focus, .modal-form-group select:focus, .modal-form-group textarea:focus {
            border-color: var(--color-primary);
        }
        .pin-toggle-btn {
            position: absolute !important;
            right: 4px !important;
            top: 50% !important;
            transform: translateY(-50%) !important;
            width: 38px !important;
            height: 38px !important;
            display: inline-flex !important;
            align-items: center !important;
            justify-content: center !important;
            background: transparent !important;
            border: none !important;
            border-radius: 8px !important;
            color: var(--text-secondary) !important;
            cursor: pointer !important;
            z-index: 5 !important;
            padding: 0 !important;
            font-size: 15px !important;
            touch-action: manipulation !important;
            user-select: none !important;
            transition: color 0.15s ease, background 0.15s ease, transform 0.1s ease !important;
        }
        .pin-toggle-btn:hover {
            color: var(--color-primary) !important;
            background: rgba(255, 255, 255, 0.08) !important;
        }
        .pin-toggle-btn:active {
            transform: translateY(-50%) scale(0.92) !important;
            color: var(--color-primary) !important;
        }
        .pin-toggle-btn i {
            pointer-events: none !important;
        }
        .modal-footer {
            display: flex;
            justify-content: flex-end;
            gap: 10px;
            margin-top: 25px;
            border-top: 1px solid var(--border-card);
            padding-top: 15px;
        }
        .modal-btn {
            padding: 10px 20px;
            border-radius: 20px;
            font-weight: bold;
            font-family: Inter;
            font-size: 14px;
            cursor: pointer;
            transition: 0.3s;
            border: 1px solid var(--color-primary);
        }
        .modal-btn-primary {
            background: var(--btn-bg);
            color: var(--btn-text);
            border-color: var(--color-primary);
        }
        .modal-btn-primary:hover {
            box-shadow: var(--shadow-primary);
            transform: translateY(-2px);
        }
        .modal-btn-secondary {
            background: var(--bg-input);
            color: var(--text-secondary);
            border-color: var(--border-card);
        }
        .modal-btn-secondary:hover {
            background: var(--nav-hover-bg);
        }
        .modal-grid-2 {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 15px;
        }
        .readonly-value {
            background: var(--bg-input);
            border: 1px solid var(--border-card) !important;
            color: var(--text-secondary) !important;
            cursor: not-allowed;
        }
        .preview-box {
            background: var(--nav-hover-bg);
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 15px;
            font-size: 14px;
            line-height: 1.6;
            margin-top: 15px;
        }
        .preview-row {
            display: flex;
            justify-content: space-between;
            border-bottom: 1px dashed var(--border-card);
            padding: 6px 0;
        }
        .preview-row:last-child {
            border-bottom: none;
        }
        .preview-label {
            color: var(--text-secondary);
            font-weight: bold;
        }
        .preview-val {
            color: var(--text-primary);
            text-align: right;
        }
        .btn-icon-edit {
            background: transparent;
            border: none;
            color: var(--text-heading);
            cursor: pointer;
            font-size: 16px;
            padding: 5px;
            margin-left: 10px;
            transition: 0.3s;
        }
        .btn-icon-edit:hover {
            transform: scale(1.1);
            color: var(--color-primary);
        }
        @keyframes slideIn {
            from { transform: translateX(120%); opacity: 0; }
            to { transform: translateX(0); opacity: 1; }
        }
        @keyframes slideOut {
            from { transform: translateX(0); opacity: 1; }
            to { transform: translateX(120%); opacity: 0; }
        }
        .btn-refresh-history {
            background: var(--nav-active-bg);
            border: 1px solid var(--border-color);
            color: var(--text-heading);
            cursor: pointer;
            font-size: 13px;
            font-weight: 600;
            padding: 6px 14px;
            border-radius: 20px;
            display: inline-flex;
            align-items: center;
            gap: 6px;
            transition: all 0.3s ease;
            font-family: 'Inter', sans-serif;
        }
        .btn-refresh-history:hover {
            background: var(--nav-hover-bg);
            border-color: var(--color-primary);
            color: var(--text-primary);
            box-shadow: var(--shadow-primary);
            transform: translateY(-1px);
        }
        .btn-refresh-history:active {
            transform: translateY(0);
        }

        /* Floating sidebar button on the left for homework shortcut */
        .homework-shortcut-left {
            position: fixed;
            left: 20px;
            top: calc(constant(safe-area-inset-top, 0px) + 90px);
            top: calc(env(safe-area-inset-top, 0px) + 90px);
            z-index: 999;
        }
        
        .hw-btn-left {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            width: 100px;
            height: 100px;
            background: var(--bg-card-alt);
            border: 1px solid var(--border-color);
            border-radius: 18px;
            color: #FFF;
            text-decoration: none !important;
            font-weight: 700;
            font-size: 11.5px;
            gap: 10px;
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            box-shadow: 
                0 10px 30px rgba(0,0,0,0.6),
                inset 0 0 15px rgba(142, 77, 255, 0.2);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            cursor: pointer;
            text-align: center;
            padding: 10px;
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        }
        
        .hw-btn-left i {
            font-size: 26px;
            color: var(--text-heading);
            text-shadow: 0 0 10px rgba(255, 210, 63, 0.5);
            transition: transform 0.3s;
        }
        
        .hw-btn-left span {
            color: var(--text-primary);
            line-height: 1.3;
        }
        
        .hw-btn-left:hover {
            background: var(--nav-active-bg);
            border-color: var(--color-primary);
            transform: scale(1.08) translateX(5px);
            box-shadow: var(--shadow-primary);
        }
        
        .hw-btn-left:hover i {
            transform: translateY(-4px) rotate(-10deg) scale(1.1);
        }

        @media (max-width: 1024px) {
            .homework-shortcut-left {
                display: none !important;
            }
        }

        /* ================= TUTOR HOMEWORK MANAGEMENT SYSTEM ================= */
        .tutor-hw-tab {
            background: transparent;
            border: none;
            color: var(--text-secondary);
            padding: 10px 20px;
            font-size: 14px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s;
            border-bottom: 2px solid transparent;
            display: flex;
            align-items: center;
            gap: 8px;
            font-family: 'Inter', sans-serif;
        }
        .tutor-hw-tab:hover {
            color: var(--text-primary);
        }
        .tutor-hw-tab.active {
            color: var(--color-primary);
            border-bottom-color: var(--color-primary);
        }
        .tutor-hw-tab-content {
            animation: fadeIn 0.3s ease-in-out;
        }
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(5px); }
            to { opacity: 1; transform: translateY(0); }
        }

        /* Sub-tab buttons (Tải bài tập lên / Xem bài tập đã tải) */
        .tutor-hw-subtab {
            padding: 8px 18px;
            border-radius: 20px;
            font-weight: 600;
            font-family: 'Inter', sans-serif;
            font-size: 13px;
            cursor: pointer;
            transition: all 0.3s ease;
            border: 1px solid var(--border-card);
            background: var(--bg-input);
            color: var(--text-secondary);
            display: inline-flex;
            align-items: center;
            gap: 8px;
            height: 38px;
            box-sizing: border-box;
            outline: none;
        }
        .tutor-hw-subtab:hover {
            background: var(--nav-hover-bg);
            color: var(--text-primary);
            border-color: var(--border-color);
        }
        .tutor-hw-subtab.active {
            background: var(--btn-bg);
            color: var(--btn-text);
            border-color: var(--color-primary);
            box-shadow: var(--shadow-primary);
        }

        /* Action button style (Thùng rác bài tập, Tải về...) */
        .action-btn-hw {
            background: var(--bg-input);
            border: 1px solid var(--border-card);
            color: var(--text-secondary);
            padding: 6px 14px;
            border-radius: 20px; /* Bo góc tròn viên thuốc hoàn hảo */
            font-size: 12px;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 6px;
            outline: none;
            font-family: 'Inter', sans-serif;
            box-sizing: border-box;
        }
        .action-btn-hw:hover {
            background: var(--nav-hover-bg);
            color: var(--text-primary);
            border-color: var(--color-primary);
            transform: translateY(-1px);
        }
        .action-btn-hw.btn-delete:hover {
            background: rgba(239, 68, 68, 0.2);
            color: #FFF;
            border-color: #EF4444;
            transform: translateY(-1px);
        }

        /* Icon action buttons in tables (Edit, Delete) styled as circles */
        .action-btn-hw-icon {
            width: 32px;
            height: 32px;
            border-radius: 50%; /* Tròn xoe cực đẹp */
            display: inline-flex;
            align-items: center;
            justify-content: center;
            cursor: pointer;
            transition: all 0.3s ease;
            border: 1px solid var(--border-card);
            background: var(--bg-input);
            color: var(--text-secondary);
            padding: 0;
            outline: none;
            box-sizing: border-box;
        }
        .action-btn-hw-icon:hover {
            transform: translateY(-2px);
            box-shadow: 0 4px 10px rgba(0,0,0,0.25);
        }
        .action-btn-hw-edit {
            border-color: rgba(255, 159, 67, 0.3);
            background: rgba(255, 159, 67, 0.1);
            color: #FF9F43;
        }
        .action-btn-hw-edit:hover {
            border-color: #FF9F43;
            background: rgba(255, 159, 67, 0.2);
            color: #FFF;
        }
        .action-btn-hw-delete {
            border-color: rgba(239, 68, 68, 0.3);
            background: rgba(239, 68, 68, 0.1);
            color: #EF4444;
        }
        .action-btn-hw-delete:hover {
            border-color: #EF4444;
            background: rgba(239, 68, 68, 0.2);
            color: #FFF;
        }

        /* Responsive Mobile Enhancements */
        @media (max-width: 768px) {
            /* 1. Student Buttons scrollable container instead of ugly wrap/center */
            .student-buttons-container {
                flex-wrap: nowrap !important;
                overflow-x: auto !important;
                justify-content: flex-start !important;
                padding: 5px 20px 15px 20px !important;
                margin-left: -20px !important;
                margin-right: -20px !important;
                gap: 10px !important;
                scrollbar-width: none !important;
                -webkit-overflow-scrolling: touch;
            }
            .student-buttons-container::-webkit-scrollbar {
                display: none !important;
            }
            .student-btn {
                flex-shrink: 0 !important;
                padding: 10px 18px !important;
                font-size: 13px !important;
            }

            /* 2. Grid systems inside modals to single column */
            .modal-grid-2 {
                grid-template-columns: 1fr !important;
                gap: 12px !important;
            }

            /* 3. Sub-tabs flex buttons to occupy space nicely */
            .tutor-hw-subtab {
                flex: 1;
                justify-content: center;
                min-width: 130px;
                padding: 8px 12px !important;
                font-size: 12px !important;
            }
        }

        /* Định kiểu màu trắng cho con mắt hiển thị mật khẩu của trình duyệt */
        input::-ms-reveal, input::-ms-clear {
            filter: invert(100%) brightness(1.5) !important;
        }
        input::-webkit-contacts-auto-fill-button, 
        input::-webkit-credentials-auto-fill-button {
            filter: invert(100%) brightness(1.5) !important;
        }

        /* Dòng chữ chạy thông báo mượt mà (GPU accelerated) & Sticky nổi bồng bềnh */
        .smooth-marquee-container {
            position: sticky;
            top: 10px; /* Ghim cách mép trên màn hình 10px cực kỳ cao cấp */
            z-index: 1000;
            background: var(--bg-card); /* Che nội dung cuộn bên dưới */
            backdrop-filter: blur(12px); /* Hiệu ứng kính mờ glassmorphism */
            border: 1px solid var(--border-color);
            border-radius: 12px;
            padding: 12px 16px;
            margin: 0 0 20px 0;
            overflow: hidden;
            box-shadow: var(--shadow-card); /* Đổ bóng mạnh để nổi lên trên các thẻ bên dưới */
            display: none;
        }
        .smooth-marquee-wrapper {
            width: 100%;
            overflow: hidden;
            white-space: nowrap;
            box-sizing: border-box;
        }
        .smooth-marquee-content {
            display: inline-block;
            padding-left: 100%;
            animation: smoothMarqueeScroll 18s linear infinite; /* Thời gian chạy 18 giây theo yêu cầu */
            color: var(--text-heading);
            font-size: 15.5px; /* Kích thước chữ to nổi bật */
            font-weight: 800; /* Chữ siêu đậm */
            font-family: 'Inter', sans-serif;
            vertical-align: middle;
            letter-spacing: 0.5px;
        }
        @keyframes smoothMarqueeScroll {
            0% {
                transform: translate3d(0, 0, 0);
            }
            100% {
                transform: translate3d(-100%, 0, 0);
            }
        }

        /* Hiển thị có điều kiện vùng nộp bài Desktop / Mobile của Gia sư */
        @media (min-width: 769px) {
            #tutorHwUploadAreaMobile { display: none !important; }
            #tutorHwUploadAreaDesktop { display: block !important; }
            #demoHwUploadAreaMobile { display: none !important; }
            #demoHwUploadAreaDesktop { display: block !important; }
        }
        @media (max-width: 768px) {
            #tutorHwUploadAreaMobile { display: block !important; }
            #tutorHwUploadAreaDesktop { display: none !important; }
            #demoHwUploadAreaMobile { display: block !important; }
            #demoHwUploadAreaDesktop { display: none !important; }
        }

        /* Standalone PWA & iOS App Support */
        @media all and (display-mode: standalone) {
            .header {
                padding-top: max(52px, calc(env(safe-area-inset-top, 0px) + 14px)) !important;
            }
            #resultBox, #tutorDashboardBox, #adminDashboardBox {
                padding-top: max(52px, calc(env(safe-area-inset-top, 0px) + 14px)) !important;
            }
            .container {
                padding-top: max(52px, calc(env(safe-area-inset-top, 0px) + 14px)) !important;
            }
        }
        
        .is-pwa-standalone .header,
        .is-ios-device.is-pwa-standalone .header {
            padding-top: max(52px, calc(env(safe-area-inset-top, 0px) + 14px)) !important;
        }
        .is-pwa-standalone #resultBox,
        .is-pwa-standalone #tutorDashboardBox,
        .is-pwa-standalone #adminDashboardBox {
            padding-top: max(52px, calc(env(safe-area-inset-top, 0px) + 14px)) !important;
        }

        /* TOAST & NOTIFICATION NOTCH PROTECTION */
        #toastContainer,
        .toast-container {
            position: fixed !important;
            top: 24px;
            right: 24px;
            z-index: 999999 !important;
            display: flex;
            flex-direction: column;
            gap: 10px;
            pointer-events: none;
            max-width: 480px;
        }

        @media (max-width: 768px) {
            #toastContainer,
            .toast-container {
                top: max(60px, calc(env(safe-area-inset-top, 0px) + 18px)) !important;
                left: 50% !important;
                right: auto !important;
                transform: translateX(-50%) !important;
                width: calc(100% - 32px) !important;
                max-width: 420px !important;
                align-items: center !important;
            }
            #toastContainer > div,
            .toast-container > div {
                width: 100% !important;
                box-sizing: border-box !important;
                justify-content: center !important;
                text-align: center !important;
            }
        }

        @media all and (display-mode: standalone) {
            #toastContainer,
            .toast-container {
                top: max(65px, calc(env(safe-area-inset-top, 0px) + 24px)) !important;
            }
        }

        .is-pwa-standalone #toastContainer,
        .is-pwa-standalone .toast-container,
        .is-ios-device #toastContainer,
        .is-ios-device .toast-container {
            top: max(65px, calc(env(safe-area-inset-top, 0px) + 24px)) !important;
        }

        /* ==========================================================================
           FIXED VIEWPORT CHO TAB LỊCH DẠY (TRIỆT TIÊU HOÀN TOÀN THANH CUỘN NGOÀI CÙNG)
           ========================================================================== */
        html.calendar-tab-active,
        body.calendar-tab-active {
            height: 100vh !important;
            max-height: 100vh !important;
            overflow: hidden !important;
        }

        body.calendar-tab-active .tutor-app-layout {
            height: 100vh !important;
            max-height: 100vh !important;
            overflow: hidden !important;
        }

        body.calendar-tab-active .tutor-main-content {
            height: 100vh !important;
            max-height: 100vh !important;
            overflow: hidden !important;
            padding: 14px 20px 14px 20px !important;
            display: flex !important;
            flex-direction: column !important;
            box-sizing: border-box !important;
        }

        body.calendar-tab-active #tutorSectionCalendar {
            flex: 1 !important;
            height: 100% !important;
            min-height: 0 !important;
            max-height: 100% !important;
            display: flex !important;
            flex-direction: column !important;
            overflow: hidden !important;
            margin: 0 !important;
            padding: 0 !important;
        }

        body.calendar-tab-active .calendar-embed-wrapper {
            flex: 1 !important;
            height: 100% !important;
            max-height: 100% !important;
            min-height: 520px !important;
            overflow: hidden !important;
            margin: 0 !important;
        }

        body.calendar-tab-active #tutorCalendarIframe {
            flex: 1 !important;
            height: 100% !important;
            width: 100% !important;
            min-height: 520px !important;
            border: none !important;
            display: block !important;
        }

        /* ===========================
           PHASE 14 — GLOBAL MOBILE POLISH
           =========================== */

        /* 1. Prevent iOS auto-zoom khi focus input (font < 16px gây zoom) */
        @media (max-width: 768px) {
            input[type="text"],
            input[type="password"],
            input[type="number"],
            input[type="email"],
            input[type="tel"],
            input[type="search"],
            select,
            textarea {
                font-size: 16px !important;
            }
        }

        /* 2. Touch target tối thiểu 44px (Apple HIG guideline) */
        @media (max-width: 768px) {
            .nav-btn,
            .btn-submit,
            .btn-cta,
            .action-btn-hw,
            .mobile-nav-item,
            button[onclick],
            .btn-quick {
                min-height: 44px !important;
                min-width: 44px !important;
            }
            .btn-small {
                padding: 10px 16px !important;
                min-height: 44px !important;
            }
        }

        /* 3. Prevent horizontal overflow toàn trang */
        body { overflow-x: hidden; }

        /* 4. Smooth scroll */
        html { scroll-behavior: smooth; }
        @media (prefers-reduced-motion: reduce) {
            html { scroll-behavior: auto; }
            * { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
        }

        /* 5. Hero section mobile (index.html) */
        @media (max-width: 480px) {
            .hero-title { font-size: 26px !important; line-height: 1.3 !important; }
            .hero-subtitle { font-size: 14px !important; }
            .hero-ctas { flex-direction: column !important; gap: 10px !important; width: 100% !important; }
            .btn-cta { width: 100% !important; justify-content: center !important; }
            .hero-badge { font-size: 11px !important; padding: 6px 12px !important; }
        }

        /* 6. Login card mobile (student-login + tutor-login) */
        @media (max-width: 480px) {
            .search-card { padding: 20px 16px !important; border-radius: 16px !important; }
            .main-title { font-size: 24px !important; }
            .sub-title { font-size: 14px !important; }
        }

        /* 7. Safe area sticky bars */
        .sticky-bottom-bar {
            padding-bottom: calc(12px + env(safe-area-inset-bottom)) !important;
        }

        /* 8. Tutor Dashboard Mobile Refinements */
        @media (max-width: 580px) {
            #tutorQuickAnnouncementWidget {
                padding: 12px !important;
            }
            #tutorQuickAnnouncementWidget > div:last-child {
                flex-direction: column !important;
            }
            #quickAnnouncementInput {
                width: 100% !important;
                min-width: 0 !important;
                box-sizing: border-box !important;
            }
            #btnSaveQuickAnnouncement {
                width: 100% !important;
                justify-content: center !important;
            }
            .overview-top-bar {
                flex-direction: column !important;
                align-items: stretch !important;
                gap: 10px !important;
            }
            .month-selector-widget {
                width: 100% !important;
                justify-content: space-between !important;
            }
            .diary-filters, .tuition-filters {
                flex-direction: column !important;
                align-items: stretch !important;
                gap: 8px !important;
            }
            .diary-filter-item, .tuition-filter-item {
                width: 100% !important;
                box-sizing: border-box !important;
                justify-content: space-between !important;
            }
            .diary-filter-item select, .tuition-filter-item select {
                flex: 1;
                min-width: 0;
            }
        }

/* ===== PHASE 17 — BOTTOM NAVIGATION ===== */
.bottom-nav { display: none; }

body.logged-in .bottom-nav,
.logged-in .bottom-nav,
.bottom-nav.hidden-nav,
.bottom-nav[style*="display: none"],
.bottom-nav[style*="display:none"] {
  display: none !important;
}

@media (max-width: 768px) {
  .bottom-nav {
    display: flex !important;
    position: fixed !important;
    bottom: 0 !important;
    left: 0 !important;
    right: 0 !important;
    width: 100% !important;
    max-width: 100vw !important;
    box-sizing: border-box !important;
    overflow: hidden !important;
    height: calc(60px + env(safe-area-inset-bottom, 0px)) !important;
    padding-bottom: env(safe-area-inset-bottom, 0px) !important;
    background: rgba(255, 255, 255, 0.97) !important;
    backdrop-filter: blur(20px) !important;
    -webkit-backdrop-filter: blur(20px) !important;
    border-top: 1px solid #E2E8F0 !important;
    box-shadow: 0 -4px 20px rgba(0, 0, 0, 0.06) !important;
    z-index: 9000 !important;
    align-items: center !important;
    justify-content: space-around !important;
  }
  body.logged-in .bottom-nav,
  .logged-in .bottom-nav,
  .bottom-nav.hidden-nav,
  .bottom-nav[style*="display: none"],
  .bottom-nav[style*="display:none"] {
    display: none !important;
  }
  .bottom-nav-item {
    display: flex !important;
    flex-direction: column !important;
    align-items: center !important;
    justify-content: center !important;
    gap: 3px !important;
    padding: 6px 2px !important;
    text-decoration: none !important;
    border-radius: 12px !important;
    transition: all 0.2s !important;
    flex: 1 1 0 !important;
    width: 25% !important;
    max-width: 25% !important;
    min-width: 0 !important;
    box-sizing: border-box !important;
    min-height: 48px !important;
    position: relative !important;
    -webkit-tap-highlight-color: transparent !important;
  }
  .bottom-nav-item i {
    font-size: 20px !important;
    color: #94A3B8 !important;
    transition: color 0.2s, transform 0.2s !important;
  }
  .bottom-nav-item span {
    font-size: 10px !important;
    font-weight: 600 !important;
    color: #94A3B8 !important;
    font-family: Inter, sans-serif !important;
    white-space: nowrap !important;
    text-overflow: ellipsis !important;
    overflow: hidden !important;
    max-width: 100% !important;
    text-align: center !important;
    transition: color 0.2s !important;
  }
  .bottom-nav-item.active i  { color: #3B82F6 !important; transform: scale(1.1) !important; }
  .bottom-nav-item.active span { color: #3B82F6 !important; }
  .bottom-nav-item.active { background: rgba(59, 130, 246, 0.08) !important; }
  .bottom-nav-item:active { transform: scale(0.94) !important; }

  /* Ẩn hamburger + desktop nav + dropdown cũ */
  .hamburger-btn        { display: none !important; }
  .nav-right            { display: none !important; }
  .mobile-nav-dropdown  { display: none !important; }

  /* Padding bottom để content không bị bottom nav che */
  body { padding-bottom: calc(68px + env(safe-area-inset-bottom, 0px)) !important; }
  body.logged-in { padding-bottom: 24px !important; }
}

/* ===== PHASE 17 — HEADER COMPACT ===== */
@media (max-width: 768px) {
  .header {
    padding: 8px 16px !important;
    min-height: 52px !important;
  }
  .nav-logo { width: 32px !important; height: 32px !important; }
  .header-text h1 { font-size: 14px !important; margin: 0 !important; }
  .header-text p  { display: none !important; }
  .nav-container  { min-height: 52px !important; }
  .nav-install-btn {
    height: 34px !important;
    min-height: 34px !important;
    padding: 0 13px !important;
    font-size: 12.5px !important;
    border-radius: 20px !important;
    gap: 5px !important;
    margin-left: auto !important;
    box-shadow: 0 3px 10px rgba(37, 99, 235, 0.25) !important;
  }
  .nav-install-btn i {
    font-size: 12px !important;
  }
}
@media (max-width: 480px) {
  .header { padding: 6px 12px !important; min-height: 48px !important; }
  .header-text h1 { font-size: 13px !important; }
  .nav-install-btn {
    height: 31px !important;
    min-height: 31px !important;
    padding: 0 11px !important;
    font-size: 11.5px !important;
    border-radius: 16px !important;
    gap: 4px !important;
  }
  .nav-install-btn i {
    font-size: 11px !important;
  }
}

/* ===== PHASE 17 — TYPOGRAPHY ===== */
@media (max-width: 480px) {
  html { -webkit-text-size-adjust: 100%; }
  input, select, textarea { font-size: 16px !important; }

  /* Hero section index.html */
  .hero-title  { font-size: 24px !important; line-height: 1.3 !important; }
  .hero-subtitle { font-size: 14px !important; }
  .hero-ctas { flex-direction: column !important; gap: 10px !important; }
  .btn-cta { width: 100% !important; justify-content: center !important; }
}
@media (max-width: 360px) {
  .hero-title { font-size: 20px !important; }
}

/* ===== PHASE 17 — GLOBAL POLISH ===== */

/* Smooth scroll */
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* Prevent horizontal overflow */
body {
  overflow-x: hidden;
  max-width: 100%;
}

/* Better tap experience */
@media (max-width: 768px) {
  button, a, [onclick], label {
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
  }

  /* Active press animation */
  button:active,
  .hw-kpi-card:active,
  .summary-card:active,
  .hw-assigned-card:active,
  .bottom-nav-item:active {
    transform: scale(0.95) !important;
    transition: transform 0.08s ease !important;
  }

  /* Touch targets 44px — KHÔNG dùng "button" chung, chỉ class cụ thể */
  .nav-btn, .btn-submit, .btn-cta,
  .bottom-nav-item, .action-btn-hw,
  .hw-logout-btn, .hw-btn-preview,
  .hw-btn-edit, .hw-btn-del,
  .btn-submit-feedback, .btn-back,
  .btn-load-more, .legend-btn {
    min-height: 44px !important;
  }

  /* Font 16px input — chỉ context public pages, không override Tailwind */
  .search-card input, .search-card select, .search-card textarea,
  #hwLessonInput, #hwStudentInput,
  .feedback-form-container textarea,
  input[type="text"]:not([class*="text-"]),
  input[type="password"]:not([class*="text-"]) {
    font-size: 16px !important;
  }

  /* Scrollbar nhỏ */
  ::-webkit-scrollbar { width: 3px; height: 3px; }
  ::-webkit-scrollbar-thumb { background: #CBD5E1; border-radius: 4px; }
}

/* iOS safe area cho bottom nav */
@media (max-width: 768px) {
  .bottom-nav {
    padding-bottom: max(12px, env(safe-area-inset-bottom, 0px)) !important;
    height: calc(60px + max(12px, env(safe-area-inset-bottom, 0px))) !important;
  }
}

/* Skeleton loading class (có thể dùng sau) */
.skeleton {
  background: linear-gradient(90deg, #F1F5F9 25%, #E2E8F0 50%, #F1F5F9 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: 8px;
}
@keyframes skeleton-shimmer {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ============================================================
 * PHASE 19 — SCROLL REVEAL ANIMATIONS (Cuộn đến đâu hiện đến đó)
 * ============================================================ */

/* Fade + trượt lên từ dưới */
.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}
.reveal.visible {
  opacity: 1 !important;
  transform: translateY(0) !important;
  will-change: auto;
}

/* Stagger: Các thẻ con trượt lên so le lần lượt */
.reveal-stagger > * {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.55s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.55s cubic-bezier(0.16, 1, 0.3, 1) !important;
  will-change: opacity, transform;
}
.reveal-stagger.visible > * {
  opacity: 1 !important;
  transform: translateY(0) !important;
  will-change: auto;
}
.reveal-stagger.visible > *:nth-child(1) { transition-delay: 0.05s !important; }
.reveal-stagger.visible > *:nth-child(2) { transition-delay: 0.15s !important; }
.reveal-stagger.visible > *:nth-child(3) { transition-delay: 0.25s !important; }
.reveal-stagger.visible > *:nth-child(4) { transition-delay: 0.35s !important; }
.reveal-stagger.visible > *:nth-child(5) { transition-delay: 0.45s !important; }
.reveal-stagger.visible > *:nth-child(6) { transition-delay: 0.55s !important; }
.reveal-stagger.visible > *:nth-child(7) { transition-delay: 0.65s !important; }
.reveal-stagger.visible > *:nth-child(8) { transition-delay: 0.75s !important; }
.reveal-stagger.visible > *:nth-child(9) { transition-delay: 0.85s !important; }
.reveal-stagger.visible > *:nth-child(10) { transition-delay: 0.95s !important; }

/* Trượt từ bên trái sang */
.reveal-left {
  opacity: 0;
  transform: translateX(-40px);
  transition: opacity 0.65s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.65s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}
.reveal-left.visible {
  opacity: 1 !important;
  transform: translateX(0) !important;
  will-change: auto;
}

/* Trượt từ bên phải sang */
.reveal-right {
  opacity: 0;
  transform: translateX(40px);
  transition: opacity 0.65s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.65s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}
.reveal-right.visible {
  opacity: 1 !important;
  transform: translateX(0) !important;
  will-change: auto;
}

/* Phóng to nhẹ (Scale in) */
.reveal-scale {
  opacity: 0;
  transform: scale(0.92);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
  will-change: opacity, transform;
}
.reveal-scale.visible {
  opacity: 1 !important;
  transform: scale(1) !important;
  will-change: auto;
}

/* Mobile: giảm khoảng cách translate */
@media (max-width: 480px) {
  .reveal        { transform: translateY(20px); }
  .reveal-stagger > * { transform: translateY(20px); }
  .reveal-left   { transform: translateX(-20px); }
  .reveal-right  { transform: translateX(20px); }
  .reveal-scale  { transform: scale(0.94); }
}

/* Badge môn học (subj-chip) theo chuẩn giao diện demo */
.subj-chip {
    background: #F0FDF4;
    color: #15803D;
    border: 1px solid #BBF7D0;
    border-radius: 8px;
    padding: 3px 10px;
    font-size: 12px;
    font-weight: 600;
    display: inline-block;
    white-space: nowrap;
}
[data-theme="dark"] .subj-chip {
    background: rgba(16, 185, 129, 0.15);
    color: #34D399;
    border-color: rgba(16, 185, 129, 0.3);
}

/* ============================================================================
 * PILL LOGIN & SEARCH FORMS RESPONSIVE (TỐI ƯU GIAO DIỆN NÚT TRÊN ĐIỆN THOẠI)
 * ============================================================================ */
.btn-text-portal {
  display: inline;
}

@media (max-width: 640px) {
  #formBaiTap,
  #formPhHs {
    padding: 5px 6px !important;
    box-shadow: 0 8px 25px -4px rgba(37, 99, 235, 0.15) !important;
  }

  #formBaiTap > div:first-child,
  #formPhHs > div:first-child {
    padding-left: 10px !important;
    padding-right: 6px !important;
    flex-shrink: 0 !important;
  }

  #formBaiTap > div:first-child svg,
  #formPhHs > div:first-child svg {
    width: 19px !important;
    height: 19px !important;
  }

  #formBaiTap input,
  #formPhHs input {
    font-size: 13.5px !important;
    padding: 8px 4px !important;
    min-width: 0 !important;
    line-height: 1.3 !important;
  }

  #btnSubmitBaiTap,
  #btnSubmitPhHs {
    padding: 8px 14px !important;
    font-size: 13px !important;
    border-radius: 9999px !important;
    gap: 5px !important;
    min-height: 38px !important;
    max-height: 40px !important;
    flex-shrink: 0 !important;
  }

  #btnSubmitBaiTap .btn-icon,
  #btnSubmitPhHs .btn-icon,
  #btnSubmitBaiTap .loading-icon,
  #btnSubmitPhHs .loading-icon {
    width: 15px !important;
    height: 15px !important;
  }

  .btn-text-portal {
    display: none !important;
  }
}

@media (max-width: 420px) {
  #formBaiTap,
  #formPhHs {
    padding: 4px 5px !important;
  }

  #formBaiTap > div:first-child,
  #formPhHs > div:first-child {
    padding-left: 8px !important;
    padding-right: 4px !important;
  }

  #formBaiTap > div:first-child svg,
  #formPhHs > div:first-child svg {
    width: 17px !important;
    height: 17px !important;
  }

  #formBaiTap input,
  #formPhHs input {
    font-size: 13px !important;
    padding: 6px 4px !important;
  }

  #btnSubmitBaiTap,
  #btnSubmitPhHs {
    padding: 7px 11px !important;
    font-size: 12px !important;
    gap: 4px !important;
    min-height: 35px !important;
    max-height: 37px !important;
  }

  #btnSubmitBaiTap .btn-icon,
  #btnSubmitPhHs .btn-icon,
  #btnSubmitBaiTap .loading-icon,
  #btnSubmitPhHs .loading-icon {
    width: 13px !important;
    height: 13px !important;
  }
}

/* ============================================================
 * TASK 1 — Card Hover Effects & Micro-interactions
 * ============================================================ */

/* KPI Cards hover (Tutor Dashboard) */
.tutor-kpi-card,
.kpi-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease !important;
}
.tutor-kpi-card:hover,
.kpi-card:hover {
    transform: translateY(-4px) !important;
    box-shadow: 0 12px 28px rgba(0, 0, 0, 0.12), 0 4px 10px rgba(0, 0, 0, 0.08) !important;
}
.tutor-kpi-card:hover .kpi-icon-wrapper,
.tutor-kpi-card:hover .kpi-icon,
.kpi-card:hover .kpi-icon {
    transform: scale(1.15);
    transition: transform 0.3s ease;
}

/* Schedule cards hover */
.upcoming-day-card,
.schedule-card,
.upcoming-schedule-item {
    transition: transform 0.3s ease, box-shadow 0.3s ease !important;
}
.upcoming-day-card:hover,
.schedule-card:hover,
.upcoming-schedule-item:hover {
    transform: translateY(-3px) !important;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.1) !important;
}

/* Student & Tuition cards hover */
.student-card,
.student-item-btn,
.tuition-banner-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease !important;
}
.student-card:hover,
.student-item-btn:hover,
.tuition-banner-card:hover {
    transform: translateY(-3px) !important;
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.1) !important;
}

/* Overview Charts & Summary Boxes */
.overview-chart-box,
.student-revenue-box,
.summary-card,
.donut-card,
.chart-card,
.feedback-card {
    transition: transform 0.3s ease, box-shadow 0.3s ease !important;
}
.overview-chart-box:hover,
.student-revenue-box:hover,
.summary-card:hover,
.donut-card:hover,
.chart-card:hover {
    transform: translateY(-3px) !important;
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.1) !important;
}

/* Disable hover on touch/mobile devices */
@media (hover: none) {
    .tutor-kpi-card:hover,
    .kpi-card:hover,
    .upcoming-day-card:hover,
    .schedule-card:hover,
    .student-card:hover,
    .overview-chart-box:hover,
    .summary-card:hover,
    .donut-card:hover,
    .chart-card:hover {
        transform: none !important;
        box-shadow: inherit !important;
    }
}

/* ============================================================
 * TASK 2 — Loading Skeleton & Empty State
 * ============================================================ */

@keyframes skeletonShimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

.skeleton {
    background: linear-gradient(
        90deg,
        var(--bg-card-alt, #e2e8f0) 25%,
        var(--border-color, #f1f5f9) 50%,
        var(--bg-card-alt, #e2e8f0) 75%
    ) !important;
    background-size: 200% 100% !important;
    animation: skeletonShimmer 1.5s ease-in-out infinite !important;
    border-radius: 8px;
}

.skeleton-text {
    height: 14px;
    margin-bottom: 8px;
    width: 80%;
}
.skeleton-text.short { width: 40%; }
.skeleton-text.medium { width: 60%; }

.skeleton-circle {
    border-radius: 50%;
}

.skeleton-card {
    padding: 20px;
    border-radius: 16px;
    background: var(--bg-card, #fff);
    border: 1px solid var(--border-color, #e2e8f0);
}

/* KPI Skeleton */
.skeleton-kpi-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 16px;
    margin-bottom: 20px;
}
@media (max-width: 768px) {
    .skeleton-kpi-grid { grid-template-columns: repeat(2, 1fr); }
}

.skeleton-kpi-card {
    padding: 20px;
    border-radius: 16px;
    background: var(--bg-card, #fff);
    border: 1px solid var(--border-color, #e2e8f0);
}
.skeleton-kpi-card .skeleton-icon {
    width: 40px; height: 40px;
    border-radius: 12px;
    margin-bottom: 12px;
}
.skeleton-kpi-card .skeleton-value {
    height: 28px; width: 60%; margin-bottom: 8px;
}
.skeleton-kpi-card .skeleton-label {
    height: 12px; width: 80%;
}

/* Chart Skeleton */
.skeleton-chart-box {
    padding: 24px;
    border-radius: 16px;
    background: var(--bg-card, #fff);
    border: 1px solid var(--border-color, #e2e8f0);
    min-height: 250px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.skeleton-chart-bars {
    display: flex;
    align-items: flex-end;
    gap: 8px;
    height: 180px;
    padding-top: 20px;
}
.skeleton-bar {
    flex: 1;
    border-radius: 6px 6px 0 0;
}

/* Table Skeleton */
.skeleton-table {
    width: 100%;
}
.skeleton-table-row {
    display: flex;
    gap: 16px;
    padding: 14px 0;
    border-bottom: 1px solid var(--border-color, #e2e8f0);
}
.skeleton-table-row .skeleton-cell {
    height: 16px;
    flex: 1;
}

/* Empty State */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    text-align: center;
    width: 100%;
}
.empty-state-icon {
    font-size: 48px;
    margin-bottom: 16px;
    opacity: 0.5;
    color: var(--color-primary, #3B82F6);
}
.empty-state-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary, #1e293b);
    margin-bottom: 6px;
}
.empty-state-desc {
    font-size: 13.5px;
    color: var(--text-secondary, #64748b);
    max-width: 360px;
    line-height: 1.5;
    margin-bottom: 16px;
}
.empty-state-btn {
    padding: 9px 20px;
    border-radius: 10px;
    background: var(--btn-bg, #3B82F6);
    color: var(--btn-text, #fff);
    border: none;
    font-weight: 700;
    font-size: 13px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    transition: 0.3s;
}
.empty-state-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

/* ============================================================
 * TASK 4 — Progress Comparison & Achievement Badges
 * ============================================================ */

.progress-compare-box {
    background: var(--bg-card, #fff);
    border: 1px solid var(--border-color, #e2e8f0);
    border-radius: 16px;
    padding: 20px;
    margin-bottom: 24px;
}

.progress-compare-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
    gap: 12px;
}
@media (max-width: 768px) {
    .progress-compare-grid { grid-template-columns: repeat(2, 1fr); }
}

.progress-compare-item {
    text-align: center;
    padding: 14px 10px;
    border-radius: 12px;
    background: var(--bg-card-alt, #f8fafc);
    border: 1px solid var(--border-color, #e2e8f0);
    transition: transform 0.25s ease;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    min-height: 82px;
}
.progress-compare-item:hover {
    transform: translateY(-2px);
}
.progress-compare-item .compare-label {
    font-size: 11.5px;
    color: var(--text-secondary, #64748b);
    margin-bottom: 6px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}
.progress-compare-item .compare-values {
    font-size: 15px;
    font-weight: 800;
    color: var(--text-primary, #1e293b);
}
.progress-compare-item .compare-arrow {
    font-size: 13px;
    font-weight: 700;
    margin-top: 4px;
}
.compare-arrow.up { color: #10B981; }
.compare-arrow.down { color: #EF4444; }
.compare-arrow.same { color: #94A3B8; }

/* ============================================================
 * TASK 5 — Profile Avatar & Cropper (Facebook style)
 * ============================================================ */

.profile-avatar-section {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 12px 0 8px;
}

.profile-avatar-wrapper {
    width: 100px;
    height: 100px;
    border-radius: 50%;
    position: relative;
    cursor: pointer;
    overflow: visible;
}

.profile-avatar-img {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    object-fit: cover;
    border: 3px solid var(--color-primary, #3B82F6);
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.3);
}

.profile-avatar-placeholder {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    background: var(--bg-card-alt, #e2e8f0);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-secondary, #94a3b8);
    border: 3px dashed var(--border-color, #cbd5e1);
}

.profile-avatar-edit-btn {
    position: absolute;
    bottom: 2px;
    right: 2px;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--btn-bg, #3B82F6);
    color: #fff;
    border: 2px solid var(--bg-card, #fff);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 13px;
    transition: 0.25s ease;
    box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}
.profile-avatar-edit-btn:hover {
    transform: scale(1.15);
}

/* Crop zoom & rotate buttons */
.crop-zoom-btn {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    border: 1px solid var(--border-color, #e2e8f0);
    background: var(--bg-card, #fff);
    color: var(--text-primary, #1e293b);
    font-size: 14px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: 0.2s;
}
.crop-zoom-btn:hover {
    background: var(--color-primary, #3B82F6);
    color: #fff;
}

/* Cropper.js circular crop overlay */
#avatarCropModal {
    z-index: 2500 !important;
}
#avatarCropModal .cropper-view-box,
#avatarCropModal .cropper-face {
    border-radius: 50%;
}
#avatarCropModal .cropper-view-box {
    outline: 2px solid #3B82F6;
    outline-offset: -2px;
}

/* Sidebar avatar */
.sidebar-avatar {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}
.sidebar-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 50%;
    display: block;
}

/* ============================================================
 * TASK 6 — Settings Modal & Dark Mode
 * ============================================================ */

.settings-section {
    padding: 16px 0;
    border-bottom: 1px solid var(--border-color, #e2e8f0);
}
.settings-section:last-of-type { border-bottom: none; }

.settings-section-title {
    font-size: 14.5px;
    font-weight: 700;
    color: var(--text-primary, #1e293b);
    margin: 0 0 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}
.settings-section-title i {
    color: var(--color-primary, #3B82F6);
}

.settings-toggle-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 0;
    gap: 16px;
}
.settings-toggle-label {
    font-size: 13.5px;
    font-weight: 600;
    color: var(--text-primary, #1e293b);
    display: block;
}
.settings-toggle-desc {
    font-size: 12px;
    color: var(--text-secondary, #64748b);
    display: block;
    margin-top: 2px;
}

/* Toggle Switch */
.toggle-switch {
    position: relative;
    width: 46px;
    height: 25px;
    flex-shrink: 0;
    display: inline-block;
}
.toggle-switch input { opacity: 0; width: 0; height: 0; }
.toggle-slider {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: #CBD5E1;
    border-radius: 25px;
    cursor: pointer;
    transition: 0.3s ease;
}
.toggle-slider:before {
    content: '';
    position: absolute;
    height: 19px; width: 19px;
    left: 3px; bottom: 3px;
    background: #fff;
    border-radius: 50%;
    transition: 0.3s ease;
    box-shadow: 0 2px 5px rgba(0,0,0,0.2);
}
.toggle-switch input:checked + .toggle-slider {
    background: var(--color-primary, #3B82F6);
}
.toggle-switch input:checked + .toggle-slider:before {
    transform: translateX(21px);
}

/* Settings action button */
.settings-action-btn {
    padding: 8px 18px;
    border-radius: 9px;
    background: var(--btn-bg, #3B82F6);
    color: var(--btn-text, #fff);
    border: none;
    font-weight: 700;
    font-size: 13px;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: 0.25s;
    margin-top: 6px;
}
.settings-action-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

/* Theme grid in settings */
.settings-theme-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}
.settings-theme-dot {
    width: 26px; height: 26px;
    border-radius: 50%;
    border: 2px solid transparent;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    position: relative;
}
.settings-theme-dot:hover {
    transform: scale(1.2);
}
.settings-theme-dot.active {
    border-color: var(--text-primary, #1e293b);
    box-shadow: 0 0 0 2px var(--bg-card, #fff), 0 0 0 4px var(--color-primary, #3B82F6);
}

/* Dark mode explicit overrides */
[data-dark-mode="true"] {
    --bg-page: #0B0F19 !important;
    --bg-card: #151D2F !important;
    --bg-card-alt: #1E293B !important;
    --bg-input: #1E293B !important;
    --text-primary: #F8FAFC !important;
    --text-secondary: #94A3B8 !important;
    --border-color: #334155 !important;
    --border-card: #334155 !important;
    --shadow-card: 0 4px 16px rgba(0,0,0,0.4) !important;
}

/* ============================================================
 * TASK 7 — Onboarding Tour
 * ============================================================ */
.onboarding-backdrop {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: transparent;
    z-index: 9997;
    pointer-events: auto;
}

.onboarding-spotlight {
    position: fixed;
    z-index: 9998;
    border-radius: 16px;
    border: 2.5px solid var(--color-primary, #3B82F6);
    /* Lớp phủ tối nhẹ xung quanh, khoét lỗ vùng được hướng dẫn 100% trong suốt, sáng rõ nét, không che mờ chữ */
    box-shadow: 0 0 0 9999px rgba(15, 23, 42, 0.42), 0 0 20px rgba(59, 130, 246, 0.4);
    pointer-events: none;
    transition: all 0.3s cubic-bezier(0.25, 1, 0.5, 1);
    display: none;
    box-sizing: border-box;
}

.onboarding-tooltip {
    position: fixed;
    z-index: 10000;
    background: var(--bg-card, #fff);
    border-radius: 16px;
    padding: 20px 24px;
    max-width: 380px;
    width: calc(100vw - 40px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.35), 0 0 0 1px var(--border-color, #e2e8f0);
    animation: tooltipAppear 0.3s ease;
}

@keyframes tooltipAppear {
    0% { opacity: 0; transform: translateY(10px); }
    100% { opacity: 1; transform: translateY(0); }
}

.onboarding-tooltip-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.onboarding-step-count {
    font-size: 12px;
    font-weight: 700;
    color: var(--color-primary, #3B82F6);
    background: rgba(59, 130, 246, 0.12);
    padding: 3px 10px;
    border-radius: 20px;
}

.onboarding-skip-btn {
    font-size: 12px;
    color: var(--text-secondary, #94a3b8);
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px 8px;
    border-radius: 6px;
}

.onboarding-skip-btn:hover {
    color: var(--text-primary, #1e293b);
}

.onboarding-title {
    font-size: 16px;
    font-weight: 800;
    color: var(--text-primary, #1e293b);
    margin: 0 0 6px;
}

.onboarding-desc {
    font-size: 13px;
    color: var(--text-secondary, #64748b);
    line-height: 1.6;
    margin: 0 0 16px;
}

.onboarding-footer {
    display: flex;
    justify-content: space-between;
    gap: 10px;
}

.onboarding-btn {
    padding: 8px 18px;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 700;
    cursor: pointer;
    border: none;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: 0.2s;
}

.onboarding-btn-primary {
    background: var(--btn-bg, #3B82F6);
    color: #fff;
}

.onboarding-btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.onboarding-btn-secondary {
    background: var(--bg-card-alt, #f1f5f9);
    color: var(--text-primary, #1e293b);
}

.onboarding-btn-secondary:hover {
    background: var(--border-color, #e2e8f0);
}

.onboarding-highlight {
    position: relative;
    z-index: 9999 !important;
    box-shadow: 0 0 0 4px var(--color-primary, #3B82F6), 0 0 0 8px rgba(59, 130, 246, 0.25) !important;
    border-radius: 12px;
    transition: box-shadow 0.3s;
}

@media (max-width: 768px) {
    .onboarding-spotlight {
        border-width: 2px;
        box-shadow: 0 0 0 9999px rgba(15, 23, 42, 0.48), 0 0 16px rgba(59, 130, 246, 0.45);
    }
    .onboarding-tooltip {
        padding: 14px 16px;
        border-radius: 18px;
        box-shadow: 0 16px 48px rgba(0, 0, 0, 0.45), 0 0 0 1px var(--border-color, #e2e8f0);
        left: 14px !important;
        right: 14px !important;
        width: calc(100vw - 28px) !important;
        max-width: calc(100vw - 28px) !important;
        box-sizing: border-box;
    }
    .onboarding-title {
        font-size: 15px;
        font-weight: 800;
        line-height: 1.35;
        margin: 0 0 6px 0;
    }
    .onboarding-desc {
        font-size: 12.5px;
        line-height: 1.55;
        margin: 0 0 14px 0;
    }
    .onboarding-footer {
        gap: 8px;
    }
    .onboarding-btn {
        padding: 8px 14px;
        font-size: 12.5px;
        min-height: 38px;
        border-radius: 10px;
    }
    .onboarding-step-count {
        font-size: 11px;
        padding: 2.5px 8px;
    }
    .onboarding-skip-btn {
        font-size: 11.5px;
        padding: 4px 6px;
    }
}