/* ============================================
   تِك عربي - Clean Modern Design
   Hostinger-Inspired Color Scheme
   ============================================ */

/* CSS Variables - Light Theme (Hostinger Style) */
:root {
    /* Primary Purple - Hostinger Style */
    --primary-color: #673DE6;
    --primary-dark: #5025D1;
    --primary-light: #8B5CF6;
    --primary-lighter: #EDE9FE;

    /* Secondary Colors */
    --secondary-color: #673DE6;
    --accent-color: #673DE6;

    /* Backgrounds - Clean White */
    --bg-color: #FFFFFF;
    --bg-secondary: #F9FAFB;
    --bg-tertiary: #F3F4F6;
    --card-bg: #FFFFFF;

    /* Text - Easy to Read */
    --text-color: #1F1F1F;
    --text-secondary: #4B5563;
    --text-light: #6B7280;
    --text-muted: #9CA3AF;

    /* Borders */
    --border-color: #E5E7EB;
    --border-light: #F3F4F6;

    /* Status Colors */
    --success-color: #10B981;
    --success-light: #D1FAE5;
    --warning-color: #F59E0B;
    --warning-light: #FEF3C7;
    --error-color: #EF4444;
    --error-light: #FEE2E2;
    --info-color: #673DE6;
    --info-light: #EDE9FE;

    /* Code Blocks */
    --code-bg: #1F2937;
    --code-header: #374151;
    --code-text: #F9FAFB;

    /* Shadows - Subtle */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);

    /* Border Radius */
    --radius-sm: 4px;
    --radius: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-full: 9999px;

    /* Typography */
    --font-arabic: 'Cairo', 'Segoe UI', sans-serif;
    --font-code: 'Fira Code', 'Consolas', monospace;

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition: 0.2s ease;
    --transition-slow: 0.3s ease;

    /* Layout */
    --navbar-height: 72px;
    --sidebar-width: 280px;
    --toc-width: 260px;
}

/* Dark Theme - Clean Dark */
[data-theme="dark"] {
    --bg-color: #111827;
    --bg-secondary: #1F2937;
    --bg-tertiary: #374151;
    --card-bg: #1F2937;

    --text-color: #F9FAFB;
    --text-secondary: #D1D5DB;
    --text-light: #9CA3AF;
    --text-muted: #6B7280;

    --border-color: #374151;
    --border-light: #1F2937;

    --code-bg: #0F172A;
    --code-header: #1E293B;

    --success-light: #064E3B;
    --warning-light: #78350F;
    --error-light: #7F1D1D;
    --info-light: #312E81;

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4);
}

/* ============================================
   Reset & Base Styles
   ============================================ */

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: calc(var(--navbar-height) + 20px);
}

body {
    font-family: var(--font-arabic);
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.7;
    direction: rtl;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.container-narrow {
    max-width: 800px;
    margin: 0 auto;
    padding: 0 24px;
}

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

ul, ol {
    list-style: none;
}

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

code {
    font-family: var(--font-code);
    background: var(--bg-tertiary);
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-size: 0.9em;
    color: var(--primary-color);
    direction: ltr;
    display: inline-block;
}

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

::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--text-muted);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-light);
}

/* ============================================
   Typography
   ============================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.3;
    color: var(--text-color);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
}

strong {
    font-weight: 600;
    color: var(--text-color);
}

/* ============================================
   Navbar - Clean & Simple
   ============================================ */

.navbar {
    background: var(--bg-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    height: var(--navbar-height);
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-color);
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
}

.logo-img {
    height: 40px;
    width: auto;
    max-width: 180px;
    object-fit: contain;
}

.logo:hover .logo-img {
    opacity: 0.9;
}

.nav-links {
    display: flex;
    gap: 8px;
}

.nav-links a {
    color: var(--text-secondary);
    font-weight: 500;
    padding: 10px 16px;
    border-radius: var(--radius);
    transition: all var(--transition-fast);
}

.nav-links a:hover {
    color: var(--primary-color);
    background: var(--primary-lighter);
}

.nav-links a.active {
    color: var(--primary-color);
    background: var(--primary-lighter);
    font-weight: 600;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.theme-toggle {
    width: 40px;
    height: 40px;
    border-radius: var(--radius);
    border: 1px solid var(--border-color);
    background: var(--bg-color);
    color: var(--text-color);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.auth-buttons {
    display: flex;
    gap: 8px;
}

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    width: 40px;
    height: 40px;
    border-radius: var(--radius);
    border: none;
    background: transparent;
    color: var(--text-color);
    cursor: pointer;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    z-index: 1001;
}

.mobile-menu-btn span {
    width: 22px;
    height: 2px;
    background: var(--text-color);
    border-radius: 2px;
    transition: all var(--transition-fast);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* Mobile Navigation */
.mobile-nav-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(--transition);
}

.mobile-nav-overlay.active {
    opacity: 1;
}

.mobile-nav {
    display: none;
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    max-width: 85%;
    height: 100vh;
    background: var(--bg-color);
    z-index: 1000;
    padding: 80px 24px 24px;
    box-shadow: var(--shadow-xl);
    transition: right var(--transition);
    overflow-y: auto;
}

.mobile-nav.active {
    right: 0;
}

.mobile-nav-links {
    display: flex;
    flex-direction: column;
    gap: 4px;
    margin-bottom: 24px;
}

.mobile-nav-links a {
    display: block;
    padding: 14px 16px;
    color: var(--text-color);
    font-weight: 500;
    border-radius: var(--radius);
    transition: all var(--transition-fast);
}

.mobile-nav-links a:hover,
.mobile-nav-links a.active {
    background: var(--primary-lighter);
    color: var(--primary-color);
}

.mobile-nav-divider {
    height: 1px;
    background: var(--border-color);
    margin: 16px 0;
}

.mobile-auth-buttons {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.mobile-auth-buttons .btn {
    width: 100%;
    justify-content: center;
}

/* ============================================
   Hero Section - Clean & Modern
   ============================================ */

.hero {
    background: var(--bg-color);
    padding: 80px 0 100px;
    text-align: center;
    position: relative;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--primary-lighter);
    color: var(--primary-color);
    padding: 8px 20px;
    border-radius: var(--radius-full);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 24px;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 20px;
    color: var(--text-color);
    line-height: 1.2;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 40px;
    line-height: 1.7;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    margin-top: 60px;
    padding-top: 40px;
    border-top: 1px solid var(--border-color);
}

.hero-stat {
    text-align: center;
}

.hero-stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    display: block;
}

.hero-stat-label {
    font-size: 1rem;
    color: var(--text-light);
}

/* ============================================
   Buttons - Clean Style
   ============================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition);
    border: none;
    font-family: var(--font-arabic);
    text-decoration: none;
}

.btn-lg {
    padding: 16px 32px;
    font-size: 1.1rem;
}

.btn-sm {
    padding: 8px 16px;
    font-size: 0.9rem;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

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

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

.btn-success:hover {
    background: #059669;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    padding: 10px 16px;
}

.btn-ghost:hover {
    background: var(--bg-secondary);
    color: var(--primary-color);
}

/* ============================================
   Stats Section
   ============================================ */

.stats {
    padding: 60px 0;
    background: var(--bg-secondary);
}

.stats .container {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.stat-card {
    background: var(--bg-color);
    padding: 32px 24px;
    border-radius: var(--radius-lg);
    text-align: center;
    transition: all var(--transition);
    border: 1px solid var(--border-color);
}

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

.stat-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    margin: 0 auto 16px;
}

.stat-icon.blue { background: var(--primary-lighter); color: var(--primary-color); }
.stat-icon.green { background: var(--success-light); color: var(--success-color); }
.stat-icon.yellow { background: var(--warning-light); color: var(--warning-color); }
.stat-icon.purple { background: var(--primary-lighter); color: var(--primary-color); }

.stat-number {
    display: block;
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-color);
    line-height: 1;
}

.stat-label {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-top: 8px;
}

/* ============================================
   Courses Section
   ============================================ */

.courses-section {
    padding: 80px 0;
    background: var(--bg-color);
}

.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 24px;
    margin-top: 48px;
}

.course-card {
    background: var(--bg-color);
    border-radius: var(--radius-lg);
    padding: 32px;
    border: 1px solid var(--border-color);
    text-align: center;
    transition: all var(--transition);
    position: relative;
}

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

.course-card.coming-soon {
    opacity: 0.6;
}

.course-card.coming-soon::before {
    content: 'قريباً';
    position: absolute;
    top: 16px;
    left: -28px;
    background: var(--warning-color);
    color: white;
    padding: 4px 36px;
    font-size: 0.8rem;
    font-weight: 600;
    transform: rotate(-45deg);
}

.course-icon {
    width: 72px;
    height: 72px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    font-weight: 700;
    font-family: var(--font-code);
    margin: 0 auto 20px;
    color: white;
}

.course-icon-sql {
    background: var(--primary-color);
}

.course-icon-python {
    background: linear-gradient(135deg, #3776AB, #FFD43B);
    color: #3776AB;
}

.course-icon-etl {
    background: var(--success-color);
}

.course-card h3 {
    font-size: 1.35rem;
    margin-bottom: 12px;
}

.course-card p {
    color: var(--text-secondary);
    margin-bottom: 24px;
    font-size: 0.95rem;
}

.course-stats {
    display: flex;
    justify-content: center;
    gap: 32px;
    margin-bottom: 24px;
    padding: 16px 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.course-stat {
    text-align: center;
}

.course-stat-value {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-color);
}

.course-stat-label {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ============================================
   CTA Section
   ============================================ */

.cta-section {
    padding: 80px 0;
    background: var(--primary-color);
    color: white;
    text-align: center;
}

.cta-section h2 {
    font-size: 2rem;
    margin-bottom: 16px;
    color: white;
}

.cta-section p {
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 500px;
    margin: 0 auto 32px;
    color: white;
}

.cta-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

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

.cta-section .btn-primary:hover {
    background: rgba(255,255,255,0.9);
    transform: translateY(-2px);
}

.cta-section .btn-secondary {
    background: transparent;
    border: 2px solid white;
    color: white;
}

.cta-section .btn-secondary:hover {
    background: rgba(255,255,255,0.1);
}

/* ============================================
   Lessons Section
   ============================================ */

.lessons-section {
    padding: 80px 0;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-header h2 {
    font-size: 2rem;
    margin-bottom: 12px;
}

.section-header p {
    font-size: 1.1rem;
    max-width: 500px;
    margin: 0 auto;
}

.module {
    margin-bottom: 48px;
    background: var(--bg-color);
    border-radius: var(--radius-lg);
    padding: 24px;
    border: 1px solid var(--border-color);
}

.module-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border-color);
}

.module-title {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.2rem;
    color: var(--text-color);
}

.module-icon {
    width: 40px;
    height: 40px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    font-weight: 700;
    font-family: var(--font-code);
    color: white;
    flex-shrink: 0;
}

.module-icon.intro { background: var(--primary-color); }
.module-icon.basics { background: var(--success-color); }
.module-icon.modify { background: var(--warning-color); }
.module-icon.advanced { background: var(--primary-color); }
.module-icon.expert { background: #EC4899; }

.module-progress {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 0.9rem;
    color: var(--text-light);
}

.module-progress-bar {
    width: 100px;
    height: 6px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.module-progress-fill {
    height: 100%;
    background: var(--success-color);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
}

.lessons-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 16px;
}

.lesson-card {
    background: var(--bg-secondary);
    border-radius: var(--radius);
    padding: 20px;
    display: flex;
    align-items: flex-start;
    gap: 16px;
    transition: all var(--transition);
    border: 1px solid transparent;
    position: relative;
}

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

.lesson-card.completed {
    border-color: var(--success-color);
    background: var(--bg-color);
}

.lesson-number {
    background: var(--primary-lighter);
    color: var(--primary-color);
    width: 48px;
    height: 48px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1rem;
    flex-shrink: 0;
}

.lesson-card.completed .lesson-number {
    background: var(--success-color);
    color: white;
}

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

.lesson-content h4 {
    font-size: 1rem;
    margin-bottom: 4px;
    color: var(--text-color);
    font-weight: 600;
}

.lesson-content p {
    color: var(--text-light);
    font-size: 0.9rem;
    margin: 0;
    line-height: 1.5;
}

.lesson-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 8px;
    font-size: 0.8rem;
    color: var(--text-muted);
}

.lesson-status {
    width: 24px;
    height: 24px;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-full);
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.lesson-card.completed .lesson-status {
    background: var(--success-color);
    border-color: var(--success-color);
    color: white;
}

.lesson-card.completed .lesson-status::after {
    content: '✓';
    font-size: 0.8rem;
    font-weight: 700;
}

.free-badge {
    position: absolute;
    top: 10px;
    left: 10px;
    background: var(--success-color);
    color: white;
    padding: 3px 10px;
    border-radius: var(--radius-full);
    font-size: 0.7rem;
    font-weight: 600;
}

/* ============================================
   Features Section
   ============================================ */

.features-section {
    padding: 80px 0;
    background: var(--bg-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-color);
    padding: 32px 24px;
    border-radius: var(--radius-lg);
    text-align: center;
    transition: all var(--transition);
    border: 1px solid var(--border-color);
}

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

.feature-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    background: var(--primary-lighter);
    color: var(--primary-color);
}

.feature-card h3 {
    font-size: 1.15rem;
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 0.95rem;
    margin: 0;
}

/* ============================================
   Footer
   ============================================ */

.footer {
    background: var(--text-color);
    color: white;
    padding: 60px 0 30px;
}

[data-theme="dark"] .footer {
    background: #0F172A;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand {
    max-width: 280px;
}

.footer-brand .logo-img {
    filter: brightness(0) invert(1);
    margin-bottom: 16px;
}

.footer-brand p {
    color: rgba(255,255,255,0.7);
    font-size: 0.95rem;
}

.footer-section h4 {
    color: white;
    font-size: 1rem;
    margin-bottom: 20px;
}

.footer-section ul {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-section a {
    color: rgba(255,255,255,0.7);
    transition: color var(--transition-fast);
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
    text-align: center;
    color: rgba(255,255,255,0.6);
    font-size: 0.9rem;
}

/* ============================================
   Code Blocks
   ============================================ */

.code-block {
    background: var(--code-bg);
    border-radius: var(--radius);
    margin: 24px 0;
    overflow: hidden;
    direction: ltr;
    box-shadow: var(--shadow);
}

.code-block-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: var(--code-header);
    border-bottom: 1px solid #4B5563;
}

.code-lang {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
}

.copy-btn {
    display: flex;
    align-items: center;
    gap: 6px;
    background: #4B5563;
    color: white;
    border: none;
    padding: 6px 14px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-family: var(--font-arabic);
    font-size: 0.85rem;
    font-weight: 500;
    transition: all var(--transition-fast);
}

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

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

.code-block pre {
    margin: 0;
    padding: 20px;
    overflow-x: auto;
}

.code-block code {
    font-family: var(--font-code);
    color: var(--code-text);
    font-size: 0.9rem;
    line-height: 1.7;
    display: block;
    white-space: pre;
    background: transparent;
    padding: 0;
    border-radius: 0;
}

/* Syntax Highlighting */
.keyword { color: #C084FC; font-weight: 600; }
.string { color: #86EFAC; }
.number { color: #FBBF24; }
.comment { color: #6B7280; font-style: italic; }
.function { color: #60A5FA; }
.operator { color: #F472B6; }
.table-name { color: #38BDF8; }

/* ============================================
   Info Boxes
   ============================================ */

.info-box {
    background: var(--info-light);
    border-radius: var(--radius);
    padding: 20px 24px;
    margin: 24px 0;
    border-right: 4px solid var(--info-color);
}

.info-box.warning {
    background: var(--warning-light);
    border-color: var(--warning-color);
}

.info-box.tip {
    background: var(--success-light);
    border-color: var(--success-color);
}

.info-box.danger {
    background: var(--error-light);
    border-color: var(--error-color);
}

.info-box-title {
    font-weight: 700;
    margin-bottom: 8px;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 1rem;
}

.info-box p:last-child {
    margin-bottom: 0;
}

/* ============================================
   Tables
   ============================================ */

.result-table {
    width: 100%;
    border-collapse: collapse;
    margin: 20px 0;
    background: var(--bg-color);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.result-table th {
    background: var(--primary-color);
    color: white;
    padding: 12px 16px;
    text-align: right;
    font-weight: 600;
}

.result-table td {
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-color);
}

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

.result-table tr:nth-child(even) {
    background: var(--bg-secondary);
}

.result-table tr:hover {
    background: var(--primary-lighter);
}

/* ============================================
   Lesson Page Styles
   ============================================ */

.lesson-header {
    background: var(--primary-color);
    color: white;
    padding: 48px 0;
}

.lesson-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.2);
    padding: 6px 16px;
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 12px;
}

.lesson-info h1 {
    font-size: 2rem;
    margin-bottom: 16px;
    color: white;
}

.lesson-body {
    padding: 48px 0;
}

.lesson-text {
    font-size: 1.1rem;
    line-height: 1.8;
}

.lesson-text h2 {
    margin: 48px 0 20px;
    color: var(--text-color);
    font-size: 1.5rem;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.lesson-text h2:first-child {
    margin-top: 0;
    padding-top: 0;
    border-top: none;
}

.lesson-text h3 {
    margin: 36px 0 16px;
    font-size: 1.25rem;
}

.lesson-text p {
    margin-bottom: 20px;
    color: var(--text-secondary);
}

.lesson-text ul,
.lesson-text ol {
    margin: 20px 0;
    padding-right: 24px;
}

.lesson-text ul { list-style: disc; }
.lesson-text ol { list-style: decimal; }

.lesson-text li {
    margin-bottom: 10px;
    color: var(--text-secondary);
}

.lesson-text li::marker {
    color: var(--primary-color);
}

/* Lesson Navigation */
.lesson-nav {
    display: flex;
    justify-content: space-between;
    margin-top: 48px;
    padding-top: 32px;
    border-top: 1px solid var(--border-color);
    gap: 16px;
}

.nav-btn {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 24px;
    background: var(--bg-color);
    border-radius: var(--radius);
    transition: all var(--transition);
    border: 1px solid var(--border-color);
    flex: 1;
    max-width: 260px;
}

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

.complete-section {
    text-align: center;
    margin: 48px 0;
    padding: 32px;
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
}

.complete-btn {
    background: var(--success-color);
    color: white;
    padding: 16px 40px;
    font-size: 1.1rem;
}

.complete-btn:hover {
    background: #059669;
}

/* ============================================
   Responsive Design
   ============================================ */

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

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-content {
        grid-template-columns: 1fr 1fr;
        gap: 30px;
    }
}

@media (max-width: 768px) {
    :root {
        --navbar-height: 64px;
    }

    .nav-links, .auth-buttons {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .mobile-nav,
    .mobile-nav-overlay {
        display: block;
    }

    .hero {
        padding: 60px 0 80px;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .hero-buttons {
        flex-direction: column;
        padding: 0 20px;
    }

    .hero-buttons .btn {
        width: 100%;
    }

    .hero-stats {
        flex-wrap: wrap;
        gap: 24px;
    }

    .hero-stat-number {
        font-size: 2rem;
    }

    .stats .container {
        grid-template-columns: 1fr 1fr;
        gap: 12px;
    }

    .stat-card {
        padding: 20px 16px;
    }

    .stat-number {
        font-size: 1.75rem;
    }

    .courses-grid,
    .features-grid {
        grid-template-columns: 1fr;
    }

    .section-header h2 {
        font-size: 1.5rem;
    }

    .module {
        padding: 16px;
    }

    .module-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .module-title {
        font-size: 1.05rem;
    }

    .lessons-grid {
        grid-template-columns: 1fr;
    }

    .lesson-card {
        padding: 16px;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-brand {
        max-width: 100%;
    }

    .cta-buttons {
        flex-direction: column;
        padding: 0 20px;
    }

    .cta-buttons .btn {
        width: 100%;
    }

    .code-block {
        margin: 20px -16px;
        border-radius: 0;
    }

    .lesson-nav {
        flex-direction: column;
    }

    .nav-btn {
        max-width: 100%;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .hero h1 {
        font-size: 1.75rem;
    }

    .stats .container {
        grid-template-columns: 1fr;
    }

    .stat-card {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 16px;
    }

    .stat-icon {
        margin: 0;
    }
}

/* ============================================
   Utility Classes
   ============================================ */

.text-center { text-align: center; }
.text-right { text-align: right; }
.text-left { text-align: left; }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }

.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.hidden { display: none !important; }

/* Ad Container */
.ad-container {
    margin: 32px 0;
    text-align: center;
}

.ad-slot {
    background: var(--bg-secondary);
    border: 1px dashed var(--border-color);
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    overflow: hidden;
}

.ad-leaderboard {
    min-height: 90px;
    max-width: 728px;
    margin: 0 auto;
}

.ad-rectangle {
    min-height: 250px;
    max-width: 336px;
    margin: 0 auto;
}

/* Print Styles */
@media print {
    .navbar, .footer, .lesson-nav, .complete-section, .ad-container, .theme-toggle {
        display: none !important;
    }
}