/* ============================================
   RegExpLib - Modern CSS Styles
   ============================================ */

/* CSS Variables */
:root {
    /* Colors - Cyberpunk/Terminal inspired */
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-tertiary: #1a1a25;
    --bg-card: #16161f;
    --bg-card-hover: #1e1e2a;
    
    --text-primary: #e8e8f0;
    --text-secondary: #9898a8;
    --text-muted: #606070;
    
    --accent-primary: #00ff88;
    --accent-secondary: #00d4ff;
    --accent-tertiary: #ff00aa;
    --accent-warning: #ffaa00;
    
    --gradient-primary: linear-gradient(135deg, #00ff88 0%, #00d4ff 100%);
    --gradient-secondary: linear-gradient(135deg, #00d4ff 0%, #ff00aa 100%);
    --gradient-glow: linear-gradient(135deg, rgba(0, 255, 136, 0.2) 0%, rgba(0, 212, 255, 0.2) 100%);
    
    --border-color: rgba(255, 255, 255, 0.08);
    --border-glow: rgba(0, 255, 136, 0.3);
    
    /* Typography */
    --font-display: 'Outfit', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    
    /* Spacing */
    --section-padding: clamp(60px, 10vw, 120px);
    --container-max: 1400px;
    --container-padding: clamp(20px, 5vw, 60px);
    
    /* Effects */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 20px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 40px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 30px rgba(0, 255, 136, 0.15);
    
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
    
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 30px;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-display);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
}

/* Three.js Background Canvas */
#bg-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    pointer-events: none;
}

/* Noise Overlay for texture */
.noise-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    opacity: 0.03;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
}

/* ============================================
   Navigation
   ============================================ */
.main-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 20px 0;
    background: linear-gradient(to bottom, rgba(10, 10, 15, 0.95) 0%, rgba(10, 10, 15, 0) 100%);
    backdrop-filter: blur(10px);
    transition: var(--transition-normal);
}

.main-nav.scrolled {
    background: rgba(10, 10, 15, 0.98);
    padding: 15px 0;
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 700;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 2px;
}

.logo-bracket {
    color: var(--accent-primary);
    opacity: 0.7;
}

.logo-text {
    color: var(--text-primary);
}

.logo-lib {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    gap: 40px;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    position: relative;
    transition: var(--transition-fast);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    transition: var(--transition-normal);
}

.nav-link:hover {
    color: var(--text-primary);
}

.nav-link:hover::after {
    width: 100%;
}

.nav-link.active {
    color: var(--accent-primary);
}

.nav-link.active::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 5px;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition-fast);
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    min-height: 100vh;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    padding: 120px var(--container-padding) 80px;
    max-width: var(--container-max);
    margin: 0 auto;
}

.hero-content {
    animation: fadeInUp 0.8s ease forwards;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 8px 16px;
    background: rgba(0, 255, 136, 0.1);
    border: 1px solid rgba(0, 255, 136, 0.2);
    border-radius: 50px;
    font-size: 0.85rem;
    color: var(--accent-primary);
    margin-bottom: 30px;
}

.pulse {
    width: 8px;
    height: 8px;
    background: var(--accent-primary);
    border-radius: 50%;
    animation: pulse 2s ease infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(1.2); }
}

.hero-title {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
}

.title-line {
    display: block;
}

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin-bottom: 40px;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: 16px;
    margin-bottom: 60px;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    border-radius: var(--radius-md);
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition-normal);
    border: none;
}

.btn-primary {
    background: var(--gradient-primary);
    color: var(--bg-primary);
    box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 0 40px rgba(0, 255, 136, 0.3);
}

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

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

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    padding: 10px 20px;
}

.btn-ghost:hover {
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.05);
}

/* Hero Stats */
.hero-stats {
    display: flex;
    gap: 50px;
}

.stat {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-number::after {
    content: '+';
    font-size: 1.5rem;
}

.stat:last-child .stat-number::after {
    content: '%';
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* Hero Visual */
.hero-visual {
    animation: fadeInUp 0.8s ease 0.2s forwards;
    opacity: 0;
}

.regex-showcase {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.showcase-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px 18px;
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ff5f57; }
.dot.yellow { background: #ffbd2e; }
.dot.green { background: #28ca42; }

.showcase-title {
    margin-left: 10px;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--text-muted);
}

.showcase-content {
    padding: 24px;
    overflow-x: auto;
}

.showcase-content pre {
    margin: 0;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    line-height: 1.8;
}

.showcase-content code {
    color: var(--text-primary);
}

.code-keyword { color: #ff79c6; }
.code-var { color: #8be9fd; }
.code-regex { color: var(--accent-primary); }
.code-string { color: #f1fa8c; }
.code-method { color: #50fa7b; }
.code-comment { color: var(--text-muted); font-style: italic; }

/* ============================================
   Sections Common Styles
   ============================================ */
.section-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--section-padding) var(--container-padding);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    padding: 6px 14px;
    background: rgba(0, 212, 255, 0.1);
    border: 1px solid rgba(0, 212, 255, 0.2);
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-secondary);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 20px;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    margin-bottom: 16px;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   Regex Tester Section
   ============================================ */
.tester-section {
    background: linear-gradient(180deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.tester-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
    margin-bottom: 40px;
}

.tester-panel,
.results-panel {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 30px;
}

.input-group {
    margin-bottom: 24px;
}

.input-group label {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
    font-weight: 600;
    font-size: 0.95rem;
}

.label-icon {
    font-size: 1.1rem;
}

.regex-input-wrapper {
    display: flex;
    align-items: center;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0 16px;
    transition: var(--transition-fast);
}

.regex-input-wrapper:focus-within {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(0, 255, 136, 0.1);
}

.regex-delimiter {
    font-family: var(--font-mono);
    font-size: 1.2rem;
    color: var(--accent-primary);
    font-weight: 700;
}

.regex-input-wrapper input {
    flex: 1;
    background: transparent;
    border: none;
    padding: 16px 12px;
    font-family: var(--font-mono);
    font-size: 1rem;
    color: var(--text-primary);
    outline: none;
}

.flags-input {
    width: 60px !important;
    text-align: center;
    color: var(--accent-secondary) !important;
}

#test-string {
    width: 100%;
    min-height: 200px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 16px;
    font-family: var(--font-mono);
    font-size: 0.95rem;
    color: var(--text-primary);
    resize: vertical;
    outline: none;
    transition: var(--transition-fast);
}

#test-string:focus {
    border-color: var(--accent-primary);
    box-shadow: 0 0 0 3px rgba(0, 255, 136, 0.1);
}

#test-string::placeholder {
    color: var(--text-muted);
}

.tester-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.flag-toggles {
    display: flex;
    gap: 8px;
}

.flag-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-muted);
    cursor: pointer;
    transition: var(--transition-fast);
}

.flag-btn:hover {
    border-color: var(--accent-secondary);
    color: var(--text-secondary);
}

.flag-btn.active {
    background: rgba(0, 212, 255, 0.15);
    border-color: var(--accent-secondary);
    color: var(--accent-secondary);
}

/* Results Panel */
.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border-color);
}

.results-header h3 {
    font-size: 1.1rem;
    font-weight: 600;
}

.match-count {
    padding: 6px 14px;
    background: rgba(0, 255, 136, 0.1);
    border-radius: 50px;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--accent-primary);
}

.results-output {
    min-height: 200px;
    font-family: var(--font-mono);
    font-size: 0.95rem;
    line-height: 1.8;
    white-space: pre-wrap;
    word-break: break-all;
}

.results-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 200px;
    color: var(--text-muted);
    text-align: center;
}

.results-placeholder svg {
    margin-bottom: 16px;
    opacity: 0.5;
}

.match-highlight {
    background: rgba(0, 255, 136, 0.25);
    color: var(--accent-primary);
    padding: 2px 4px;
    border-radius: 3px;
    border-bottom: 2px solid var(--accent-primary);
}

.match-details {
    margin-top: 20px;
    padding-top: 20px;
    border-top: 1px solid var(--border-color);
}

.match-item {
    display: flex;
    gap: 12px;
    padding: 10px 0;
    font-family: var(--font-mono);
    font-size: 0.85rem;
}

.match-index {
    color: var(--text-muted);
    min-width: 30px;
}

.match-value {
    color: var(--accent-primary);
}

.match-position {
    color: var(--text-muted);
    margin-left: auto;
}

/* Visualization */
.visualization-container {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.viz-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 30px;
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.viz-header h3 {
    font-size: 1rem;
    font-weight: 600;
}

.viz-controls {
    display: flex;
    gap: 8px;
}

.viz-btn {
    padding: 8px 16px;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition-fast);
}

.viz-btn:hover {
    border-color: var(--text-muted);
}

.viz-btn.active {
    background: var(--accent-primary);
    border-color: var(--accent-primary);
    color: var(--bg-primary);
}

.regex-viz {
    padding: 40px;
    min-height: 150px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow-x: auto;
}

.viz-placeholder {
    color: var(--text-muted);
    font-size: 0.95rem;
}

/* Regex Breakdown Visualization */
.regex-breakdown {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    align-items: center;
}

.regex-part {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.part-box {
    padding: 12px 16px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.95rem;
    transition: var(--transition-fast);
}

.part-box:hover {
    border-color: var(--accent-primary);
    box-shadow: 0 0 15px rgba(0, 255, 136, 0.2);
}

.part-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-align: center;
}

.part-anchor { border-color: #ff79c6; color: #ff79c6; }
.part-group { border-color: #8be9fd; color: #8be9fd; }
.part-class { border-color: #50fa7b; color: #50fa7b; }
.part-quantifier { border-color: #ffb86c; color: #ffb86c; }
.part-literal { border-color: #f1fa8c; color: #f1fa8c; }
.part-special { border-color: #bd93f9; color: #bd93f9; }

/* ============================================
   Patterns Section
   ============================================ */
.patterns-section {
    background: var(--bg-secondary);
}

.patterns-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
    margin-bottom: 50px;
}

.pattern-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: var(--transition-normal);
}

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

.pattern-icon {
    font-size: 2rem;
    margin-bottom: 16px;
}

.pattern-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.pattern-code {
    display: block;
    padding: 14px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--accent-primary);
    margin-bottom: 12px;
    overflow-x: auto;
    white-space: nowrap;
}

.pattern-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.pattern-actions {
    display: flex;
    gap: 10px;
}

.copy-btn,
.try-btn {
    flex: 1;
    padding: 10px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
}

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

.copy-btn:hover {
    border-color: var(--text-muted);
    color: var(--text-primary);
}

.try-btn {
    background: var(--gradient-primary);
    border: none;
    color: var(--bg-primary);
}

.try-btn:hover {
    opacity: 0.9;
}

.patterns-cta {
    text-align: center;
}

/* ============================================
   Learn Section
   ============================================ */
.learn-section {
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.learn-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
    margin-bottom: 60px;
}

.learn-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 32px;
    position: relative;
    overflow: hidden;
    transition: var(--transition-normal);
}

.learn-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition-normal);
}

.learn-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent-primary);
}

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

.learn-number {
    font-size: 3rem;
    font-weight: 800;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    opacity: 0.3;
    position: absolute;
    top: 20px;
    right: 24px;
}

.learn-card h3 {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
}

.learn-card p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.learn-topics {
    list-style: none;
}

.learn-topics li {
    padding: 8px 0;
    font-size: 0.9rem;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border-color);
}

.learn-topics li:last-child {
    border-bottom: none;
}

.learn-topics code {
    font-family: var(--font-mono);
    color: var(--accent-primary);
    background: rgba(0, 255, 136, 0.1);
    padding: 2px 8px;
    border-radius: 4px;
    margin-left: 8px;
}

/* Cheatsheet Preview */
.cheatsheet-preview {
    max-width: 800px;
    margin: 0 auto;
}

.cheatsheet-link {
    display: block;
    text-decoration: none;
    background: var(--gradient-glow);
    border: 1px solid var(--border-glow);
    border-radius: var(--radius-lg);
    padding: 30px 40px;
    transition: var(--transition-normal);
}

.cheatsheet-link:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

.cheatsheet-content {
    display: flex;
    align-items: center;
    gap: 24px;
}

.cheatsheet-icon {
    font-size: 3rem;
}

.cheatsheet-text {
    flex: 1;
}

.cheatsheet-text h3 {
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.cheatsheet-text p {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.cheatsheet-link svg {
    color: var(--accent-primary);
}

/* ============================================
   Footer
   ============================================ */
.main-footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
}

.footer-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 80px var(--container-padding) 60px;
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 60px;
}

.footer-brand p {
    margin-top: 20px;
    font-size: 0.95rem;
    color: var(--text-secondary);
    max-width: 300px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
}

.footer-column h4 {
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-primary);
    margin-bottom: 20px;
}

.footer-column a {
    display: block;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.95rem;
    padding: 8px 0;
    transition: var(--transition-fast);
}

.footer-column a:hover {
    color: var(--accent-primary);
}

.footer-bottom {
    text-align: center;
    padding: 30px var(--container-padding);
    border-top: 1px solid var(--border-color);
}

.footer-bottom p {
    font-size: 0.9rem;
    color: var(--text-muted);
}

.footer-bottom a {
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition-fast);
}

.footer-bottom a:hover {
    color: var(--accent-primary);
}

/* ============================================
   Animations
   ============================================ */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* Scroll animations */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        padding-top: 140px;
    }
    
    .hero-subtitle {
        margin: 0 auto 40px;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .hero-stats {
        justify-content: center;
    }
    
    .hero-visual {
        max-width: 600px;
        margin: 0 auto;
    }
    
    .tester-container {
        grid-template-columns: 1fr;
    }
    
    .footer-container {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero-actions {
        flex-direction: column;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 30px;
    }
    
    .patterns-grid {
        grid-template-columns: 1fr;
    }
    
    .learn-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
        gap: 30px;
    }
    
    .cheatsheet-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .footer-links {
        grid-template-columns: 1fr;
    }
    
    .flag-toggles {
        flex-wrap: wrap;
    }
    
    .tester-controls {
        flex-direction: column;
        gap: 16px;
    }
}

/* ============================================
   Utility Classes
   ============================================ */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-1 { margin-top: 10px; }
.mt-2 { margin-top: 20px; }
.mt-3 { margin-top: 30px; }
.mb-1 { margin-bottom: 10px; }
.mb-2 { margin-bottom: 20px; }
.mb-3 { margin-bottom: 30px; }

/* Error state */
.error {
    border-color: #ff5555 !important;
    box-shadow: 0 0 0 3px rgba(255, 85, 85, 0.2) !important;
}

.error-message {
    color: #ff5555;
    font-size: 0.85rem;
    margin-top: 8px;
}

/* Success state */
.success {
    color: var(--accent-primary);
}

/* Copy feedback */
.copied {
    position: relative;
}

.copied::after {
    content: 'Copied!';
    position: absolute;
    top: -30px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--accent-primary);
    color: var(--bg-primary);
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.8rem;
    animation: fadeInUp 0.3s ease;
}