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

:root {
    --primary-color: #6366f1;
    /* Indigo */
    --primary-hover: #4f46e5;
    --secondary-color: #a855f7;
    /* Purple */
    --success-color: #10b981;
    /* Emerald */
    --danger-color: #ef4444;
    /* Rose */
    --warning-color: #f59e0b;
    /* Amber */
    --bg-main: #f8fafc;
    /* Very light slate */
    --bg-card: #ffffff;
    --text-main: #0f172a;
    /* Slate 900 */
    --text-muted: #64748b;
    /* Slate 500 */
    --border-color: #e2e8f0;
    /* Slate 200 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);

    --bg-color: var(--bg-main);
    --text-color: var(--text-main);
    --card-bg: var(--bg-card);
    --auth-bg-gradient: radial-gradient(circle at 10% 20%, rgba(99, 102, 241, 0.05) 0%, rgba(168, 85, 247, 0.05) 90.1%);
    --table-header-bg: rgba(99, 102, 241, 0.02);
    --table-row-hover: rgba(99, 102, 241, 0.01);
}

[data-theme="dark"] {
    --bg-main: #121212;
    --bg-card: #1e1e1e;
    --text-main: #f0f0f0;
    --text-muted: #9ca3af;
    --border-color: #333333;
    --primary-color: #3b82f6;
    --primary-hover: #60a5fa;
    --secondary-color: #c084fc;
    --success-color: #34d399;
    --danger-color: #f87171;
    --warning-color: #fbbf24;

    --bg-color: var(--bg-main);
    --text-color: var(--text-main);
    --card-bg: var(--bg-card);
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.5), 0 2px 4px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.6), 0 4px 6px -4px rgba(0, 0, 0, 0.5);
    --auth-bg-gradient: radial-gradient(circle at 10% 20%, rgba(59, 130, 246, 0.15) 0%, #121212 90.1%);
    --table-header-bg: rgba(255, 255, 255, 0.05);
    --table-row-hover: rgba(255, 255, 255, 0.03);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Cairo', system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    direction: rtl;
    text-align: right;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Enable smooth transitions ONLY during active theme toggle clicks */
html.theme-animating,
html.theme-animating body,
html.theme-animating .card,
html.theme-animating .app-header,
html.theme-animating .sidebar,
html.theme-animating .table,
html.theme-animating .table th,
html.theme-animating .table td,
html.theme-animating .form-control {
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease !important;
}

/* Theme Toggle Button */
.theme-toggle-btn {
    background-color: var(--bg-main);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    width: 38px;
    height: 38px;
    min-width: 38px;
    min-height: 38px;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 1.15rem;
    flex-shrink: 0;
    user-select: none;
    outline: none;
    box-shadow: var(--shadow-sm);
    transition: transform 0.2s ease, background-color 0.2s ease;
}

.theme-toggle-btn:hover {
    background-color: var(--border-color);
    transform: scale(1.08) rotate(10deg);
    box-shadow: var(--shadow-md);
}

.theme-toggle-btn:active {
    transform: scale(0.95);
}

/* Dedicated position for login/register theme toggle */
.auth-theme-toggle {
    position: fixed;
    top: 1.25rem;
    left: 1.25rem;
    z-index: 1000;
}

/* Typography settings */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 700;
    line-height: 1.3;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-fast);
}

img, video, iframe {
    max-width: 100%;
    height: auto;
}

/* Layout */
.app-header {
    background-color: var(--bg-card);
    border-bottom: 1px solid var(--border-color);
    padding: 0.85rem 1.75rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
    backdrop-filter: blur(8px);
}

.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-wrapper h1 {
    font-size: 1.4rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-user {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.user-badge {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.1), rgba(168, 85, 247, 0.1));
    border: 1px solid rgba(99, 102, 241, 0.2);
    color: var(--primary-color);
    padding: 0.35rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.82rem;
    font-weight: 700;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.65rem 1.25rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    border: 1px solid transparent;
    cursor: pointer;
    transition: var(--transition-fast);
    font-size: 0.95rem;
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

.btn-secondary {
    background-color: transparent;
    border-color: var(--border-color);
    color: var(--text-main);
}

.btn-secondary:hover {
    background-color: var(--border-color);
}

.btn-danger {
    background-color: var(--danger-color);
    color: white;
}

.btn-danger:hover {
    background-color: #dc2626;
}

.btn-success {
    background-color: var(--success-color);
    color: white;
}

.btn-success:hover {
    background-color: #059669;
}

.btn-sm {
    padding: 0.35rem 0.75rem;
    font-size: 0.85rem;
    border-radius: 6px;
}

/* Dashboard Container */
.dashboard-container {
    display: flex;
    flex: 1;
}

/* Sidebar */
.sidebar {
    width: 250px;
    background-color: var(--bg-card);
    border-left: 1px solid var(--border-color);
    padding: 1.5rem 0.85rem;
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    flex-shrink: 0;
}

.sidebar-link {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.7rem 1rem;
    border-radius: var(--radius-sm);
    font-weight: 600;
    font-size: 0.95rem;
    color: var(--text-muted);
    transition: var(--transition-fast);
}

.sidebar-link:hover {
    background-color: rgba(99, 102, 241, 0.06);
    color: var(--primary-color);
}

.sidebar-link.active {
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary-color);
    border-right: 3px solid var(--primary-color);
    font-weight: 700;
}

/* Main Content Area */
.main-content {
    flex: 1;
    padding: 1.75rem 2rem;
    overflow-y: auto;
}

/* Card */
.card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
    margin-bottom: 1.5rem;
    transition: var(--transition-normal);
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card-title {
    font-size: 1.2rem;
    margin-bottom: 1.25rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-main);
}

/* Grid System */
.grid-cols-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
}

.grid-cols-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
}

.grid-cols-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1rem;
}

/* Stats Card */
.stat-card {
    padding: 1rem 1.15rem;
    border-radius: var(--radius-md);
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 0.85rem;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-fast);
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: rgba(99, 102, 241, 0.3);
}

.stat-icon {
    width: 44px;
    height: 44px;
    min-width: 44px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.12), rgba(168, 85, 247, 0.12));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.35rem;
    color: var(--primary-color);
}

.stat-info h3 {
    font-size: 1.45rem;
    font-weight: 800;
    margin-bottom: 0.05rem;
    color: var(--text-main);
}

.stat-info p {
    color: var(--text-muted);
    font-size: 0.82rem;
    font-weight: 600;
    white-space: nowrap;
}

/* Form Styles */
.form-group {
    margin-bottom: 1.25rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    font-size: 0.95rem;
}

.form-control {
    width: 100%;
    padding: 0.7rem 1rem;
    font-size: 0.95rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-color);
    background-color: var(--bg-main);
    color: var(--text-main);
    transition: var(--transition-fast);
    font-family: inherit;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

textarea.form-control {
    resize: vertical;
    min-height: 100px;
}

.form-check {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
}

/* Login/Register Page Specific */
.auth-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 1rem;
    background-color: var(--bg-main) !important;
    background-image: var(--auth-bg-gradient) !important;
    color: var(--text-main);
    overflow-x: hidden;
}

.auth-card {
    position: relative;
    width: 100%;
    max-width: 650px;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2.25rem 2.5rem;
    box-shadow: var(--shadow-lg);
}

.auth-card-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.85rem;
}

.auth-brand {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-weight: 800;
    font-size: 1.15rem;
}

.auth-brand-icon {
    font-size: 1.3rem;
}

.auth-brand-title {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.auth-header {
    text-align: center;
    margin-bottom: 1rem;
}

.auth-header h2 {
    font-size: 1.45rem;
    margin-bottom: 0.25rem;
    color: var(--text-main);
}

.auth-header p {
    color: var(--text-muted);
    font-size: 0.88rem;
}

/* Demo accounts interactive box */
.demo-accounts-box {
    margin-top: 1rem;
    padding: 0.75rem;
    background-color: var(--table-header-bg);
    border: 1px dashed var(--border-color);
    border-radius: var(--radius-md);
    text-align: center;
}

.demo-title {
    display: block;
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.demo-buttons {
    display: flex;
    justify-content: center;
    gap: 0.4rem;
    flex-wrap: wrap;
}

.demo-btn {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    padding: 0.35rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.78rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
    font-family: inherit;
}

.demo-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background-color: rgba(99, 102, 241, 0.08);
}

/* Custom Table System */
.table-responsive {
    overflow-x: auto;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    background-color: var(--bg-card);
    box-shadow: var(--shadow-sm);
    -webkit-overflow-scrolling: touch;
}

.table {
    width: 100%;
    border-collapse: collapse;
    text-align: right;
    font-size: 0.92rem;
}

.table th {
    font-weight: 700;
    font-size: 0.85rem;
    color: var(--text-muted);
    background-color: var(--table-header-bg);
    padding: 0.85rem 1.15rem;
    border-bottom: 1px solid var(--border-color);
    white-space: nowrap;
}

.table td {
    padding: 0.9rem 1.15rem;
    border-bottom: 1px solid var(--border-color);
    vertical-align: middle;
    color: var(--text-main);
}

.table tbody tr:last-child td {
    border-bottom: none;
}

.table tbody tr {
    transition: background-color 0.15s ease;
}

.table tbody tr:hover {
    background-color: var(--table-row-hover);
}

/* User cell layout helper */
.user-cell {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.user-avatar {
    width: 36px;
    height: 36px;
    min-width: 36px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    font-weight: 700;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
    text-transform: uppercase;
    box-shadow: var(--shadow-sm);
}

.user-cell-info {
    display: flex;
    flex-direction: column;
}

.user-cell-name {
    font-weight: 700;
    color: var(--text-main);
}

.user-cell-email {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* Badges */
.badge {
    display: inline-flex;
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 700;
    border-radius: 4px;
}

.badge-success {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
}

.badge-danger {
    background-color: rgba(239, 68, 68, 0.1);
    color: var(--danger-color);
}

.badge-warning {
    background-color: rgba(245, 158, 11, 0.1);
    color: var(--warning-color);
}

.badge-info {
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary-color);
}

/* Progress bar */
.progress-container {
    width: 100%;
    background-color: var(--border-color);
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
    margin-top: 0.5rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 4px;
    transition: width var(--transition-normal);
}

/* Sequential unlock styling */
.lesson-list-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.25rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    margin-bottom: 0.75rem;
    transition: var(--transition-fast);
    background-color: var(--bg-card);
}

.lesson-list-item.unlocked:hover {
    border-color: var(--primary-color);
    transform: translateX(-4px);
}

.lesson-list-item.locked {
    background-color: var(--border-color);
    border-color: var(--border-color);
    opacity: 0.65;
    cursor: not-allowed;
    pointer-events: none;
}

.lesson-list-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.lesson-status-icon {
    font-size: 1.25rem;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
}

.lesson-list-item.unlocked .lesson-status-icon {
    background-color: rgba(99, 102, 241, 0.1);
    color: var(--primary-color);
}

.lesson-list-item.completed .lesson-status-icon {
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--success-color);
}

.lesson-list-item.locked .lesson-status-icon {
    background-color: var(--border-color);
    color: var(--text-muted);
}

/* Alerts banners */
.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--radius-sm);
    margin-bottom: 1.5rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    border: 1px solid transparent;
}

.alert-success {
    background-color: rgba(16, 185, 129, 0.1);
    border-color: rgba(16, 185, 129, 0.2);
    color: var(--success-color);
}

.alert-danger {
    background-color: rgba(239, 68, 68, 0.1);
    border-color: rgba(239, 68, 68, 0.2);
    color: var(--danger-color);
}

.alert-info {
    background-color: rgba(99, 102, 241, 0.1);
    border-color: rgba(99, 102, 241, 0.2);
    color: var(--primary-color);
}

/* Units outline box */
.unit-section {
    margin-bottom: 2rem;
}

.unit-header {
    background: linear-gradient(135deg, rgba(99, 102, 241, 0.05) 0%, rgba(168, 85, 247, 0.05) 100%);
    border: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
    border-radius: var(--radius-sm);
    margin-bottom: 1rem;
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--primary-color);
}

/* Footer styling */
.app-footer {
    background-color: var(--bg-card);
    border-top: 1px solid var(--border-color);
    text-align: center;
    padding: 1.5rem;
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: auto;
}

/* Quiz UI custom styles */
.question-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

.question-text {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.answer-option {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    margin-bottom: 0.5rem;
    cursor: pointer;
    transition: var(--transition-fast);
}

.answer-option:hover {
    background-color: rgba(99, 102, 241, 0.04);
    border-color: var(--primary-color);
}

.answer-option input[type="radio"],
.answer-option input[type="checkbox"] {
    accent-color: var(--primary-color);
    width: 18px;
    height: 18px;
}

/* Video container */
.video-responsive {
    position: relative;
    padding-bottom: 56.25%;
    /* 16:9 ratio */
    height: 0;
    overflow: hidden;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-color);
    margin-bottom: 1.5rem;
}

.video-responsive iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/* Modals */
div[id$="-modal"] {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 9999;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

div[id$="-modal"]>div {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.75rem;
    width: 100%;
    max-width: 520px;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
}

/* ==========================================
   COMPREHENSIVE RESPONSIVE DESIGN SYSTEM
   ========================================== */

/* Laptop / Desktop medium screens (max-width: 1024px) */
@media (max-width: 1024px) {
    .app-header {
        padding: 0.85rem 1.25rem;
    }

    .grid-cols-4 {
        grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
        gap: 1rem;
    }

    .grid-cols-3 {
        grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
        gap: 1rem;
    }

    .sidebar {
        width: 220px;
        padding: 1.5rem 0.75rem;
    }

    .main-content {
        padding: 1.5rem;
    }
}

/* Tablets and Mobile Landscape (max-width: 768px) */
@media (max-width: 768px) {
    .app-header {
        padding: 0.75rem 1rem;
        flex-wrap: wrap;
        gap: 0.5rem;
    }

    .logo-wrapper h1 {
        font-size: 1.25rem;
    }

    .user-badge {
        font-size: 0.75rem;
        padding: 0.25rem 0.5rem;
    }

    .nav-user {
        gap: 0.5rem;
        font-size: 0.85rem;
    }
}

/* Mobile Hamburger ☰ Toggle Button Styling - HIDDEN BY DEFAULT on all screens */
.mobile-hamburger-btn {
    display: none;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    min-width: 38px;
    min-height: 38px;
    border-radius: var(--radius-sm);
    background-color: var(--bg-main);
    border: 1px solid var(--border-color);
    color: var(--text-main);
    font-size: 1.25rem;
    cursor: pointer;
    transition: var(--transition-fast);
    user-select: none;
    flex-shrink: 0;
}

.mobile-hamburger-btn:hover {
    background-color: var(--border-color);
    color: var(--primary-color);
}

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

/* Desktop Only Rules (min-width: 769px) - Standard Computer Layout */
@media (min-width: 769px) {
    aside.sidebar {
        position: static !important;
        transform: none !important;
        width: 250px !important;
        height: auto !important;
        box-shadow: none !important;
        z-index: 1 !important;
        padding: 1.5rem 0.85rem !important;
        border-left: 1px solid var(--border-color) !important;
        display: flex !important;
        flex-direction: column !important;
    }
    .sidebar-close-btn {
        display: none !important;
    }
    .sidebar-theme-toggle {
        display: none !important;
    }
    .mobile-hamburger-btn {
        display: none !important;
    }
    .sidebar-mobile-overlay {
        display: none !important;
    }
}

/* Off-Canvas Mobile Sidebar Drawer (max-width: 768px ONLY) */
@media (max-width: 768px) {
    .app-header {
        padding: 0.6rem 0.85rem !important;
        flex-wrap: nowrap !important;
        justify-content: space-between !important;
        gap: 0.5rem !important;
    }

    .logo-wrapper {
        gap: 0.5rem !important;
        flex-shrink: 0;
        align-items: center;
    }

    .logo-wrapper h1 {
        font-size: 1.15rem !important;
        white-space: nowrap !important;
    }

    .user-badge {
        display: none !important;
    }

    .nav-user {
        gap: 0.4rem !important;
        flex-wrap: nowrap !important;
        flex-shrink: 0;
        align-items: center;
    }

    /* Hide welcome text greeting on mobile header so header fits on 1 line */
    .nav-user > span {
        display: none !important;
    }

    .nav-user .btn-danger, .nav-user .btn-sm {
        padding: 0.35rem 0.65rem !important;
        font-size: 0.78rem !important;
        white-space: nowrap !important;
    }

    /* Hide theme toggle sun/moon button from header on mobile; available inside 3-bars sidebar */
    .theme-toggle-btn, #theme-toggle {
        display: none !important;
    }

    .mobile-hamburger-btn {
        display: inline-flex !important;
    }

    .dashboard-container {
        flex-direction: column;
    }

    /* Transform Sidebar into Off-Canvas Drawer on mobile */
    aside.sidebar {
        position: fixed !important;
        top: 0 !important;
        right: 0 !important;
        bottom: 0 !important;
        width: 280px !important;
        max-width: 85vw !important;
        height: 100vh !important;
        z-index: 99999 !important;
        background-color: var(--bg-card) !important;
        border-left: 1px solid var(--border-color) !important;
        box-shadow: -5px 0 25px rgba(0, 0, 0, 0.25) !important;
        transform: translateX(100%) !important;
        transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1) !important;
        padding: 1.25rem 1rem !important;
        display: flex !important;
        flex-direction: column !important;
        gap: 0.5rem !important;
        overflow-y: auto !important;
        margin: 0 !important;
    }

    aside.sidebar.mobile-open {
        transform: translateX(0) !important;
    }

    .sidebar-close-btn {
        display: flex !important;
        align-items: center;
        justify-content: space-between;
        padding-bottom: 0.85rem;
        margin-bottom: 0.85rem;
        border-bottom: 1px solid var(--border-color);
        font-weight: 800;
        font-size: 1.05rem;
        color: var(--text-main);
    }

    .sidebar-link {
        padding: 0.75rem 1rem;
        font-size: 0.95rem;
        border-radius: var(--radius-sm);
        background-color: transparent;
        border: none;
    }

    .sidebar-link.active {
        background-color: rgba(99, 102, 241, 0.1);
        color: var(--primary-color) !important;
        border-right: 3px solid var(--primary-color);
        font-weight: 700;
    }

    .sidebar-link[style*="margin-top: auto"] {
        margin-top: auto !important;
    }

    /* Mobile Dark Backdrop Overlay */
    .sidebar-mobile-overlay {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: rgba(0, 0, 0, 0.6);
        backdrop-filter: blur(4px);
        z-index: 99998;
        display: none;
        opacity: 0;
        transition: opacity 0.3s ease;
    }

    .sidebar-mobile-overlay.active {
        display: block;
        opacity: 1;
    }
}

/* Additional Mobile Responsive Tweaks (max-width: 768px) */
@media (max-width: 768px) {
    .main-content {
        padding: 1rem;
    }

    .card {
        padding: 1.15rem;
        margin-bottom: 1rem;
    }

    .card-title {
        font-size: 1.1rem;
        flex-wrap: wrap;
        gap: 0.5rem;
    }

    .grid-cols-4,
    .grid-cols-3,
    .grid-cols-2 {
        grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
        gap: 1rem;
    }

    .stat-card {
        padding: 1rem;
        gap: 0.85rem;
    }

    .stat-icon {
        width: 42px;
        height: 42px;
        font-size: 1.2rem;
    }

    .stat-info h3 {
        font-size: 1.4rem;
    }

    /* Table responsive behavior */
    .table-responsive {
        width: 100%;
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        border: 1px solid var(--border-color);
        border-radius: var(--radius-sm);
    }

    .table {
        min-width: 580px;
        margin-top: 0;
    }

    .table th,
    .table td {
        padding: 0.75rem 0.65rem;
        font-size: 0.85rem;
    }

    .lesson-list-item {
        padding: 0.85rem 1rem;
        flex-wrap: wrap;
        gap: 0.5rem;
    }

    .lesson-list-info {
        gap: 0.65rem;
    }
}

/* Mobile Phones Portrait (max-width: 480px) */
@media (max-width: 480px) {
    .app-header {
        padding: 0.65rem 0.75rem;
    }

    .logo-wrapper h1 {
        font-size: 1.1rem;
    }

    .nav-user span {
        max-width: 110px;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
    }

    .btn {
        padding: 0.5rem 0.85rem;
        font-size: 0.85rem;
    }

    .btn-sm {
        padding: 0.35rem 0.6rem;
        font-size: 0.78rem;
    }

    .grid-cols-4,
    .grid-cols-3,
    .grid-cols-2 {
        grid-template-columns: 1fr;
        gap: 0.85rem;
    }

    .main-content {
        padding: 0.75rem;
    }

    .card {
        padding: 1rem;
        border-radius: var(--radius-sm);
    }

    .auth-page {
        padding: 0.75rem;
    }

    .auth-card {
        padding: 1.5rem 1rem;
        border-radius: var(--radius-md);
    }

    .auth-header h2 {
        font-size: 1.35rem;
    }

    .auth-header p {
        font-size: 0.85rem;
    }

    .auth-theme-toggle {
        top: 0.75rem;
        left: 0.75rem;
        width: 34px;
        height: 34px;
        min-width: 34px;
        min-height: 34px;
        font-size: 1rem;
    }

    .form-control {
        padding: 0.65rem 0.75rem;
        font-size: 0.9rem;
    }

    .question-card {
        padding: 1rem;
    }

    .question-text {
        font-size: 0.98rem;
    }

    .answer-option {
        padding: 0.6rem 0.75rem;
        font-size: 0.88rem;
    }

    div[id$="-modal"]>div {
        padding: 1.15rem;
        max-width: 95%;
    }
}

/* Extra Small Phones (max-width: 360px) */
@media (max-width: 360px) {
    .logo-wrapper h1 {
        font-size: 1rem;
    }

    .user-badge {
        display: none;
    }

    .nav-user span {
        display: none;
    }

    .main-content {
        padding: 0.5rem;
    }
}

/* Touch-Friendly Global Enhancements */
button, select, input, a.btn {
    touch-action: manipulation;
}

/* Content Protection & Dynamic Watermark System */
.protected-content-container {
    position: relative;
    user-select: none;
    -webkit-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    overflow: hidden;
}

.protected-content-container iframe,
.protected-content-container video {
    pointer-events: auto;
}

.watermark-overlay {
    position: absolute;
    top: 20%;
    left: 20%;
    pointer-events: none;
    z-index: 999;
    background: rgba(15, 23, 42, 0.65);
    color: rgba(255, 255, 255, 0.85);
    border: 1px dashed rgba(255, 255, 255, 0.35);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.5px;
    white-space: nowrap;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.35);
    backdrop-filter: blur(3px);
    transition: all 1.8s cubic-bezier(0.4, 0, 0.2, 1);
    animation: watermarkDrift 22s infinite alternate ease-in-out;
}

@keyframes watermarkDrift {
    0% {
        top: 15%;
        left: 15%;
        opacity: 0.7;
        transform: rotate(-4deg);
    }

    25% {
        top: 70%;
        left: 25%;
        opacity: 0.9;
        transform: rotate(3deg);
    }

    50% {
        top: 30%;
        left: 65%;
        opacity: 0.6;
        transform: rotate(-2deg);
    }

    75% {
        top: 75%;
        left: 60%;
        opacity: 0.85;
        transform: rotate(4deg);
    }

    100% {
        top: 20%;
        left: 45%;
        opacity: 0.75;
        transform: rotate(-3deg);
    }
}