/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Farabi Academy Colors */
    --primary: #A8D5BA; /* Pistachio Green */
    --primary-dark: #8BC4A0;
    --primary-light: #C4E6D1;
    --primary-50: #F0F9F4;
    --secondary: #1E3A5F; /* Navy Blue */
    --secondary-dark: #152A47;
    --secondary-light: #2D4A6F;
    
    /* Status Colors */
    --success: #10B981;
    --warning: #F59E0B;
    --error: #EF4444;
    --info: #3B82F6;
    
    /* Grays */
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-400: #9CA3AF;
    --gray-500: #6B7280;
    --gray-600: #4B5563;
    --gray-700: #374151;
    --gray-800: #1F2937;
    --gray-900: #111827;
    
    /* Backgrounds */
    --bg-primary: #FFFFFF;
    --bg-secondary: #F8FAF9;
    --bg-sidebar: #FFFFFF;
    --bg-card: #FFFFFF;
    
    /* Text */
    --text-primary: #1F2937;
    --text-secondary: #6B7280;
    --text-tertiary: #9CA3AF;
    
    /* Borders */
    --border-color: #E5E7EB;
    --border-radius: 16px;
    --border-radius-sm: 12px;
    --border-radius-lg: 24px;
    --border-radius-xl: 32px;
    
    /* Soft Shadows */
    --shadow-sm: 0 2px 4px 0 rgba(30, 58, 95, 0.04);
    --shadow: 0 4px 8px 0 rgba(30, 58, 95, 0.06), 0 2px 4px 0 rgba(30, 58, 95, 0.04);
    --shadow-md: 0 8px 16px -4px rgba(30, 58, 95, 0.08), 0 4px 8px -2px rgba(30, 58, 95, 0.04);
    --shadow-lg: 0 16px 24px -6px rgba(30, 58, 95, 0.1), 0 8px 12px -4px rgba(30, 58, 95, 0.06);
    --shadow-xl: 0 24px 32px -8px rgba(30, 58, 95, 0.12), 0 12px 16px -6px rgba(30, 58, 95, 0.08);
    
    /* Spacing - Slightly reduced */
    --spacing-xs: 5px;
    --spacing-sm: 10px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    
    /* Typography - Slightly reduced */
    --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-size-xs: 11px;
    --font-size-sm: 13px;
    --font-size-base: 15px;
    --font-size-lg: 17px;
    --font-size-xl: 19px;
    --font-size-2xl: 22px;
    --font-size-3xl: 26px;
    --font-size-4xl: 32px;
    
    /* Smooth Transitions */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: all 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Animation Durations */
    --duration-fast: 150ms;
    --duration-normal: 300ms;
    --duration-slow: 500ms;
    
    /* Easing Functions */
    --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
    --ease-out: cubic-bezier(0, 0, 0.2, 1);
    --ease-in: cubic-bezier(0.4, 0, 1, 1);
    --ease-spring: cubic-bezier(0.68, -0.55, 0.265, 1.55);
}

/* Dark Mode Variables */
[data-theme="dark"] {
    /* Primary Color - Slate Blue for Dark Mode */
    --primary: #5B6B7D; /* Slate Blue */
    --primary-dark: #4A5568;
    --primary-light: #6B7A8F;
    --primary-50: #2D3748;
    
    /* Backgrounds */
    --bg-primary: #1F2937;
    --bg-secondary: #111827;
    --bg-sidebar: #1F2937;
    --bg-card: #1F2937;
    
    /* Text */
    --text-primary: #F9FAFB;
    --text-secondary: #D1D5DB;
    --text-tertiary: #9CA3AF;
    
    /* Borders */
    --border-color: #374151;
    
    /* Grays - Inverted for dark mode */
    --gray-50: #111827;
    --gray-100: #1F2937;
    --gray-200: #374151;
    --gray-300: #4B5563;
    --gray-400: #6B7280;
    --gray-500: #9CA3AF;
    --gray-600: #D1D5DB;
    --gray-700: #E5E7EB;
    --gray-800: #F3F4F6;
    --gray-900: #F9FAFB;
    
    /* Shadows - Lighter for dark mode */
    --shadow-sm: 0 2px 4px 0 rgba(0, 0, 0, 0.3);
    --shadow: 0 4px 8px 0 rgba(0, 0, 0, 0.4), 0 2px 4px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 16px -4px rgba(0, 0, 0, 0.5), 0 4px 8px -2px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 16px 24px -6px rgba(0, 0, 0, 0.6), 0 8px 12px -4px rgba(0, 0, 0, 0.5);
    --shadow-xl: 0 24px 32px -8px rgba(0, 0, 0, 0.7), 0 12px 16px -6px rgba(0, 0, 0, 0.6);
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-secondary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background-color var(--duration-normal) var(--ease-in-out),
                color var(--duration-normal) var(--ease-in-out);
}

/* RTL Support */
[dir="rtl"] {
    direction: rtl;
}

[dir="rtl"] .sidebar {
    left: auto;
    right: 0;
    border-right: none;
    border-left: 1px solid var(--border-color);
}

[dir="rtl"] .main-content {
    margin-left: 0;
    margin-right: 280px;
}

[dir="rtl"] .topbar-right {
    flex-direction: row-reverse;
}

[dir="rtl"] .notification-badge {
    right: auto;
    left: 6px;
}

[dir="rtl"] .course-info,
[dir="rtl"] .activity-item,
[dir="rtl"] .user-profile {
    flex-direction: row-reverse;
}

[dir="rtl"] .data-table th,
[dir="rtl"] .data-table td {
    text-align: right;
}

[dir="rtl"] .nav-item::before {
    left: auto;
    right: 0;
    border-radius: 2px 0 0 2px;
}

[dir="rtl"] .dark-mode-toggle::before {
    transform: translateX(0);
}

[dir="rtl"][data-theme="dark"] .dark-mode-toggle::before {
    transform: translateX(-24px);
}

[dir="rtl"] .dark-mode-toggle .sun-icon {
    left: auto;
    right: 4px;
}

[dir="rtl"] .dark-mode-toggle .moon-icon {
    right: auto;
    left: 4px;
}

[dir="rtl"] .back-btn svg {
    transform: scaleX(-1);
}

[dir="rtl"] .course-player-main {
    margin-right: 0;
}

@media (max-width: 640px) {
    [dir="rtl"] .sidebar {
        transform: translateX(100%);
    }
    
    [dir="rtl"] .sidebar.open {
        transform: translateX(0);
    }
    
    [dir="rtl"] .main-content {
        margin-right: 0;
    }
}

@media (min-width: 641px) and (max-width: 1024px) {
    [dir="rtl"] .main-content {
        margin-right: 240px;
    }
}

@media (min-width: 1025px) {
    [dir="rtl"] .main-content {
        margin-right: 280px;
    }
}

/* Dashboard Container */
.dashboard-container {
    display: flex;
    min-height: 100vh;
    background: var(--bg-secondary);
}

/* Sidebar */
.sidebar {
    width: 280px;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    left: 0;
    top: 0;
    z-index: 100;
}

.sidebar-header {
    padding: var(--spacing-xl) var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.logo-text {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--secondary);
    letter-spacing: -0.5px;
}

.logo svg {
    filter: drop-shadow(0 2px 4px rgba(30, 58, 95, 0.1));
}

.sidebar-nav {
    flex: 1;
    padding: var(--spacing-md);
    overflow-y: auto;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius);
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: var(--font-size-sm);
    transition: var(--transition);
    margin-bottom: var(--spacing-sm);
    position: relative;
}

.nav-item:hover {
    background: var(--primary-50);
    color: var(--secondary);
    transform: translateX(4px);
}

[data-theme="dark"] .nav-item:hover {
    background: var(--gray-200);
    color: white;
}

[dir="rtl"] .nav-item:hover {
    transform: translateX(-4px);
}

.nav-item.active {
    background: linear-gradient(135deg, var(--primary-50) 0%, var(--primary-light) 100%);
    color: var(--secondary);
    box-shadow: var(--shadow-sm);
}

[data-theme="dark"] .nav-item.active {
    background: var(--gray-200);
    color: var(--text-primary);
}

.nav-item.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 60%;
    background: var(--primary);
    border-radius: 0 4px 4px 0;
}

[dir="rtl"] .nav-item.active::before {
    left: auto;
    right: 0;
    border-radius: 4px 0 0 4px;
}

.nav-item svg {
    flex-shrink: 0;
}

.sidebar-footer {
    padding: var(--spacing-md);
    border-top: 1px solid var(--border-color);
}

.user-profile {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    border-radius: var(--border-radius-sm);
    background: var(--gray-50);
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    overflow: hidden;
    flex-shrink: 0;
}

.user-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

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

.user-name {
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: var(--text-primary);
    margin-bottom: 2px;
}

.user-role {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 280px;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Topbar */
.topbar {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: var(--spacing-xl) var(--spacing-2xl);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 50;
    backdrop-filter: blur(20px);
    box-shadow: var(--shadow-sm);
    transition: background-color var(--duration-normal) var(--ease-in-out),
                border-color var(--duration-normal) var(--ease-in-out);
}

/* Topbar background with transparency for light mode */
.topbar {
    background: rgba(255, 255, 255, 0.95);
}

[data-theme="dark"] .topbar {
    background: rgba(31, 41, 55, 0.95);
}

.topbar-left {
    flex: 1;
}

.page-title {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    letter-spacing: -0.5px;
    transition: color var(--duration-normal) var(--ease-in-out);
}

.page-subtitle {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    transition: color var(--duration-normal) var(--ease-in-out);
}

.topbar-right {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.topbar-right > * {
    flex-shrink: 0;
}

.icon-button {
    width: 44px;
    height: 44px;
    border-radius: var(--border-radius);
    border: none;
    background: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    position: relative;
}

.icon-button:hover {
    background: var(--primary-50);
    color: var(--secondary);
    transform: scale(1.05);
}

[data-theme="dark"] .icon-button:hover {
    background: var(--gray-200);
    color: white;
}

.icon-button:active {
    transform: scale(0.95);
}

.notification-btn {
    position: relative;
}

.notification-badge {
    position: absolute;
    top: 4px;
    right: 4px;
    width: 20px;
    height: 20px;
    background: linear-gradient(135deg, var(--error) 0%, #DC2626 100%);
    color: white;
    border-radius: 50%;
    font-size: 11px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 3px solid white;
    box-shadow: var(--shadow-sm);
}

/* Content Area */
.content-area {
    padding: var(--spacing-2xl);
    flex: 1;
}

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.stat-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-xl);
    padding: var(--spacing-xl);
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-lg);
    transition: var(--transition);
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.stat-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary) 0%, var(--primary-light) 100%);
    opacity: 0;
    transition: var(--transition);
}

.stat-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: var(--primary-light);
}

.stat-card:hover::before {
    opacity: 1;
}

.stat-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--border-radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.stat-card:hover .stat-icon {
    transform: scale(1.05) rotate(5deg);
}

.stat-content {
    flex: 1;
    min-width: 0;
}

.stat-label {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xs);
    font-weight: 500;
}

.stat-value {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xs);
    letter-spacing: -1px;
}

.stat-change {
    font-size: var(--font-size-xs);
    font-weight: 500;
}

.stat-change.positive {
    color: var(--success);
}

.stat-change.negative {
    color: var(--error);
}

/* Content Grid */
.content-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

@media (max-width: 1200px) {
    .content-grid {
        grid-template-columns: 1fr;
    }
}

/* Cards */
.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
}

.card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.card-header {
    padding: var(--spacing-xl) var(--spacing-xl) var(--spacing-lg);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.card-title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--text-primary);
}

.card-actions {
    display: flex;
    gap: var(--spacing-md);
    align-items: center;
}

.card-body {
    padding: var(--spacing-xl);
}

.chart-card {
    min-height: 400px;
}

/* Buttons */
.btn-secondary {
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-primary);
    color: var(--text-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: var(--font-size-sm);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
    text-decoration: none;
    display: inline-block;
}

.btn-secondary:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    text-decoration: none;
}

[data-theme="dark"] .btn-secondary {
    color: var(--text-primary);
    border-color: var(--border-color);
}

[data-theme="dark"] .btn-secondary:hover {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.select-input {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-sm);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: var(--font-size-sm);
    cursor: pointer;
    transition: var(--transition);
}

.select-input:hover {
    border-color: var(--gray-400);
}

[data-theme="dark"] .select-input:hover {
    border-color: var(--gray-500);
}

.select-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(168, 213, 186, 0.15);
}

[data-theme="dark"] .select-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(91, 107, 125, 0.3);
}

/* Activity List */
.activity-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.activity-item {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-lg);
    border-radius: var(--border-radius);
    transition: var(--transition);
    border: 1px solid transparent;
}

.activity-item:hover {
    background: var(--primary-50);
    border-color: var(--primary-light);
    transform: translateX(4px);
}

[dir="rtl"] .activity-item:hover {
    transform: translateX(-4px);
}

.activity-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--border-radius);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.activity-item:hover .activity-icon {
    transform: scale(1.1);
}

.activity-content {
    flex: 1;
    min-width: 0;
}

.activity-title {
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: var(--text-primary);
    margin-bottom: 2px;
}

.activity-subtitle {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.activity-time {
    font-size: var(--font-size-xs);
    color: var(--text-tertiary);
}

/* Table */
.table-container {
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
}

.data-table thead {
    background: var(--gray-50);
}

.data-table th {
    padding: var(--spacing-md);
    text-align: left;
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-bottom: 1px solid var(--border-color);
}

.data-table td {
    padding: var(--spacing-lg) var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
    font-size: var(--font-size-sm);
    color: var(--text-primary);
}

.data-table tbody tr {
    transition: var(--transition);
}

.data-table tbody tr:hover {
    background: var(--gray-50);
}

.course-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.course-thumbnail {
    /* width: 48px; */
    height: 48px;
    border-radius: var(--border-radius-sm);
    flex-shrink: 0;
}

.course-name {
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: var(--text-primary);
    margin-bottom: 2px;
}

.course-meta {
    font-size: var(--font-size-xs);
    color: var(--text-secondary);
}

.rating {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.stars {
    color: #FBBF24;
    font-size: var(--font-size-sm);
    letter-spacing: 2px;
}

.rating-value {
    font-weight: 600;
    font-size: var(--font-size-sm);
    color: var(--text-primary);
}

.badge {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 12px;
    font-size: var(--font-size-xs);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-success {
    background: var(--primary-50);
    color: var(--secondary);
    border: 1px solid var(--primary-light);
}

.badge-warning {
    background: #FEF3C7;
    color: #92400E;
}

.badge-error {
    background: #FEE2E2;
    color: #991B1B;
}

.table-actions {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

.icon-btn-small {
    width: 32px;
    height: 32px;
    border-radius: var(--border-radius-sm);
    border: none;
    background: transparent;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.icon-btn-small:hover {
    background: var(--gray-100);
    color: var(--text-primary);
}

/* Dark Mode Toggle Button */
.dark-mode-toggle {
    position: relative;
    width: 48px;
    height: 24px;
    background: var(--gray-300);
    border-radius: 12px;
    border: none;
    cursor: pointer;
    transition: background var(--duration-normal) var(--ease-in-out);
    padding: 2px;
    display: flex;
    align-items: center;
    flex-shrink: 0;
    z-index: 1;
}

.dark-mode-toggle:hover {
    background: var(--gray-400);
}

[data-theme="dark"] .dark-mode-toggle {
    background: var(--primary);
}

.dark-mode-toggle::before {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    background: white;
    border-radius: 50%;
    transition: transform var(--duration-normal) var(--ease-spring);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

[data-theme="dark"] .dark-mode-toggle::before {
    transform: translateX(24px);
}

.dark-mode-toggle svg {
    position: absolute;
    width: 14px;
    height: 14px;
    transition: opacity var(--duration-fast) var(--ease-in-out);
    color: var(--text-primary);
    z-index: 1;
}

.dark-mode-toggle .sun-icon {
    left: 4px;
    opacity: 1;
    color: #F59E0B;
}

.dark-mode-toggle .moon-icon {
    right: 4px;
    opacity: 0;
    color: var(--text-primary);
}

[data-theme="dark"] .dark-mode-toggle .sun-icon {
    opacity: 0;
}

[data-theme="dark"] .dark-mode-toggle .moon-icon {
    opacity: 1;
    color: var(--secondary);
}

/* Micro-interactions */
.card {
    transition: transform var(--duration-normal) var(--ease-out),
                box-shadow var(--duration-normal) var(--ease-out);
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    position: relative;
    overflow: hidden;
}

.btn-secondary::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width var(--duration-slow) var(--ease-out),
                height var(--duration-slow) var(--ease-out);
}

.btn-secondary:hover::before {
    width: 300px;
    height: 300px;
}

.nav-item {
    position: relative;
    transition: all var(--duration-normal) var(--ease-out);
}

.nav-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%) scaleY(0);
    width: 3px;
    height: 0;
    background: var(--primary);
    border-radius: 0 2px 2px 0;
    transition: height var(--duration-normal) var(--ease-out),
                transform var(--duration-normal) var(--ease-out);
}

.nav-item:hover::before,
.nav-item.active::before {
    height: 24px;
    transform: translateY(-50%) scaleY(1);
}

.stat-card {
    transition: transform var(--duration-normal) var(--ease-out),
                box-shadow var(--duration-normal) var(--ease-out);
}

.stat-card:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: var(--shadow-lg);
}

.icon-button {
    transition: transform var(--duration-fast) var(--ease-spring),
                background var(--duration-fast) var(--ease-in-out);
}

.icon-button:hover {
    transform: scale(1.1);
}

.icon-button:active {
    transform: scale(0.95);
}

/* Responsive Design - Mobile First */
@media (max-width: 640px) {
    :root {
        --spacing-xs: 4px;
        --spacing-sm: 8px;
        --spacing-md: 12px;
        --spacing-lg: 16px;
        --spacing-xl: 24px;
        --spacing-2xl: 32px;
    }
    
    .sidebar {
        width: 280px;
        transform: translateX(-100%);
        transition: transform var(--duration-normal) var(--ease-out);
        z-index: 1000;
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
        width: 100%;
    }
    
    .topbar {
        padding: var(--spacing-sm) var(--spacing-md);
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }
    
    .topbar-left {
        flex: 1;
        min-width: 0;
    }
    
    .page-title {
        font-size: var(--font-size-lg);
    }
    
    .page-subtitle {
        font-size: var(--font-size-xs);
    }
    
    .content-area {
        padding: var(--spacing-md);
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .content-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .card {
        margin-bottom: var(--spacing-md);
    }
    
    .card-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .course-card {
        margin-bottom: var(--spacing-md);
    }
    
    .course-player-content {
        padding: var(--spacing-md);
        grid-template-columns: 1fr !important;
    }
    
    .course-player-topbar {
        padding: var(--spacing-sm) var(--spacing-md);
        flex-wrap: wrap;
    }
    
    .language-switcher {
        order: -1;
    }
}

@media (min-width: 641px) and (max-width: 1024px) {
    .sidebar {
        width: 240px;
    }
    
    .main-content {
        margin-left: 240px;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .content-grid {
        grid-template-columns: 1fr;
    }
    
    .course-player-content {
        grid-template-columns: 1fr 300px !important;
    }
}

@media (min-width: 1025px) {
    .sidebar {
        width: 280px;
    }
    
    .main-content {
        margin-left: 280px;
    }
    
    .stats-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .content-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-300);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-400);
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

@keyframes shimmer {
    0% {
        background-position: -1000px 0;
    }
    100% {
        background-position: 1000px 0;
    }
}

.card {
    animation: fadeIn var(--duration-normal) var(--ease-out);
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Loading States */
.loading {
    position: relative;
    overflow: hidden;
}

.loading::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255, 255, 255, 0.2),
        transparent
    );
    animation: shimmer 1.5s infinite;
}

[data-theme="dark"] .loading::after {
    background: linear-gradient(
        90deg,
        transparent,
        rgba(255, 255, 255, 0.1),
        transparent
    );
}

/* Focus States for Accessibility */
*:focus-visible {
    outline: 2px solid var(--primary);
    outline-offset: 2px;
    border-radius: var(--border-radius-sm);
}

/* Selection */
::selection {
    background: var(--primary);
    color: white;
}

[data-theme="dark"] ::selection {
    background: var(--primary-light);
    color: var(--secondary);
}

/* Scrollbar Styling - Enhanced */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--gray-100);
    border-radius: 5px;
}

[data-theme="dark"] ::-webkit-scrollbar-track {
    background: var(--gray-200);
}

::-webkit-scrollbar-thumb {
    background: var(--gray-300);
    border-radius: 5px;
    transition: background var(--duration-fast) var(--ease-in-out);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-400);
}

[data-theme="dark"] ::-webkit-scrollbar-thumb {
    background: var(--gray-500);
}

[data-theme="dark"] ::-webkit-scrollbar-thumb:hover {
    background: var(--gray-400);
}

/* Language Switcher */
.language-switcher {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    background: var(--bg-primary);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-xs) var(--spacing-sm);
    transition: var(--transition);
}

.language-switcher:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-sm);
}

.language-switcher button {
    padding: var(--spacing-xs) var(--spacing-sm);
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: var(--font-size-sm);
    font-weight: 600;
    cursor: pointer;
    border-radius: var(--border-radius-sm);
    transition: var(--transition);
    min-width: 36px;
}

.language-switcher button:hover {
    background: var(--primary-50);
    color: var(--secondary);
}

.language-switcher button.active {
    background: var(--primary);
    color: white;
}

.language-switcher .divider {
    width: 1px;
    height: 20px;
    background: var(--border-color);
}

/* Cart Icon */
.cart-icon {
    position: relative;
}

.cart-badge {
    position: absolute;
    top: -4px;
    right: -4px;
    width: 18px;
    height: 18px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    font-size: 10px;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid white;
    box-shadow: var(--shadow-sm);
}

/* Print Styles */
@media print {
    .sidebar,
    .topbar {
        display: none;
    }
    
    .main-content {
        margin-left: 0;
    }
}

/* Course Player Page Styles */
.course-player-container {
    display: flex;
    min-height: 100vh;
    background: var(--bg-secondary);
}

.course-player-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    margin-left: 0;
    width: 100%;
}

.course-player-topbar {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    box-shadow: var(--shadow-sm);
    transition: background-color var(--duration-normal) var(--ease-in-out),
                border-color var(--duration-normal) var(--ease-in-out);
}

/* Course player topbar background with transparency */
.course-player-topbar {
    background: rgba(255, 255, 255, 0.95);
}

[data-theme="dark"] .course-player-topbar {
    background: rgba(31, 41, 55, 0.95);
}

.course-player-topbar .back-btn:hover {
    background: var(--gray-100);
}

[data-theme="dark"] .course-player-topbar .back-btn:hover {
    background: var(--gray-200);
}

.course-player-content {
    flex: 1;
    padding: var(--spacing-xl);
    overflow-y: auto;
}

.chapter-header:hover {
    background: var(--gray-100) !important;
}

.chapter-arrow {
    transition: transform 0.3s ease;
}

.chapter-content {
    transition: all 0.3s ease;
}

/* Theme Transition */
.theme-transitioning * {
    transition: background-color var(--duration-normal) var(--ease-in-out),
                color var(--duration-normal) var(--ease-in-out),
                border-color var(--duration-normal) var(--ease-in-out);
}

/* Mobile Menu Toggle Button */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    transition: background var(--duration-fast) var(--ease-in-out);
}

.mobile-menu-toggle:hover {
    background: var(--gray-100);
}

[data-theme="dark"] .mobile-menu-toggle:hover {
    background: var(--gray-200);
}

@media (max-width: 640px) {
    .mobile-menu-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
    }
    
    .dark-mode-toggle {
        display: flex !important;
        visibility: visible !important;
        opacity: 1 !important;
    }
}

/* Overlay for mobile sidebar */
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 999;
    opacity: 0;
    transition: opacity var(--duration-normal) var(--ease-in-out);
}

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

@media (max-width: 640px) {
    .sidebar.open ~ .sidebar-overlay {
        display: block;
        opacity: 1;
    }
}

[dir="rtl"] .sidebar-overlay {
    left: auto;
    right: 0;
}

/* Course Thumbnail Images */
.course-thumbnail {
    position: relative;
    overflow: hidden;
}

.course-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}