* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
header {
    position: fixed;
    top: 0;
    width: 100%;
    padding: 10px 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    transition: background .3s, backdrop-filter .3s;
}

header.scrolled {
    background: rgba(255, 255, 255, 0.85);
    box-shadow: 0 2px 20px rgba(0, 0, 0, .1);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo {
    display: flex;
    color: #333;
    font-size: 1.5em;
    text-decoration: none;
}

.logo-symbol {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    margin-right: 10px;
    border-radius: 50%;
    background: linear-gradient(45deg, #667eea, #764ba2);
}

.logo-symbol svg {
    width: 22px;
    height: auto;
    fill: #fff;
}

.nav-links {
    display: flex;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

.nav-links a:hover {
    color: #3b60e4;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: #3b60e4;
    transition: width 0.3s ease;
}

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

.github-btn {
    display: flex;
    align-items: center;
    background: transparent;
    color: #333;
    padding: 5px 20px;
    border-radius: 25px;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 2px solid #333;
}

.github-btn:hover {
    background: #333;
    color: white;
}

.github-btn svg {
    width: 1.25em;
    height: 1.25em;
    fill: currentColor;
    margin-right: .5em;
}

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    color: white;
    text-align: center;
    position: relative;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    overflow: hidden;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 4rem;
    margin-bottom: 20px;
    font-weight: 800;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.hero p {
    font-size: 1.3rem;
    margin-bottom: 40px;
    opacity: 0.9;
    line-height: 1.6;
}

.cta-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 15px 35px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: white;
    color: #3b60e4;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.3);
}

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

.btn-secondary:hover {
    background: white;
    color: #3b60e4;
}

/* Features Section */
.features {
    background: white;
    padding: 100px 0;
    position: relative;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin: 0 0 60px;
    color: #333;
    font-weight: 700;
}

.code-section .section-title {
    color: #fff;
}

.section-subtitle {
    margin-top: -40px;
    margin-bottom: 60px;
    color: #666; 
    font-size: 1.1rem; 
    text-align: center;
}

.code-section .section-subtitle {
    color: #ccc;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card {
    background: white;
    padding: 40px 30px;
    border-radius: 20px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid rgba(0,0,0,0.05);
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 60px rgba(0,0,0,0.15);
}

.feature-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, #667eea, #764ba2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: white;
}

.feature-icon svg {
    width: 40px;
    fill: #fff;
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: #333;
    font-weight: 600;
}

.feature-card p {
    color: #666;
    line-height: 1.6;
    font-size: 1.1rem;
}

/* Demo Section */
.demo-section {
    background: #f8f9fa;
    padding: 100px 0;
}

.demo-container {
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.1);
    margin-top: 40px;
}

.demo-tabs {
    display: flex;
    border-bottom: 2px solid #eee;
    margin-bottom: 30px;
    gap: 0;
    overflow: auto;
}

.demo-tab {
    padding: 15px 25px;
    cursor: pointer;
    border: none;
    background: none;
    font-size: 1.1rem;
    font-weight: 500;
    color: #666;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
}

.demo-tab.active {
    color: #3b60e4;
    border-bottom-color: #3b60e4;
}

.demo-content {
    min-height: 300px;
}

.demo-editor {
    border: 2px solid #eee;
    border-radius: 10px;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    white-space: nowrap; 
    clip: rect(0 0 0 0); 
    clip-path: inset(50%);
    overflow: hidden;
}

.demo-editor textarea {
    min-height: 250px;
    border: none;
    outline: none;
    font-family: inherit;
}

/* Code Section */
.code-section {
    background: #1a1a1a;
    padding: 100px 0;
    color: white;
}

.code-container {
    background: #2d2d2d;
    border-radius: 15px;
    padding: 30px;
    margin-top: 40px;
    position: relative;
    overflow-x: auto;
}

.code-header {
    display: flex;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid #444;
}

.code-dots {
    display: flex;
    gap: 8px;
}

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

.dot.red { background: #ff5f56; }
.dot.yellow { background: #ffbd2e; }
.dot.green { background: #27ca3f; }

.code-title {
    margin-left: 15px;
    color: #ccc;
    font-size: 0.9rem;
}

pre {
    background: transparent;
    border: none;
    color: #e6e6e6;
    font-size: 0.95rem;
    line-height: 1.6;
    overflow-x: auto;
}

.copy-btn {
    position: absolute;
    top: 15px;
    right: 15px;
    background: #3b60e4;
    color: white;
    border: none;
    padding: 8px 15px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: all 0.3s ease;
}

.copy-btn:hover {
    background: #667eea;
}

/* Footer */
footer {
    background: #333;
    color: white;
    text-align: center;
    padding: 40px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
    color: #ddd;
}

.footer-content a {
    color: #ddd;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-content a:hover {
    color: white;
    text-decoration: underline;
    text-underline-offset: 0.25em;
}

.footer-links {
    display: flex;
    gap: 30px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero h1 { font-size: 2.5rem; }
    .hero p { font-size: 1.1rem; }
    .cta-buttons { flex-direction: column; align-items: center; }
    .nav-links { display: none; }
    .features-grid { grid-template-columns: 1fr; }
    .footer-content { flex-direction: column; text-align: center; }
}

@media (max-width: 640px) {
    .features, .demo-section, .code-section { padding: 50px 0; }
    .section-subtitle { margin-bottom: 40px; }
    .demo-container, .code-container { padding: 15px; }
    .code-dots { gap: 5px; }
    .dot { width :8px; height: 8px }
    .code-title { margin-left: 10px; }
    .copy-btn { top: 10px; right: 10px; padding: 5px 15px; }
}

/* Syntax highlighting */
.hljs-tag { color: #f92672; }
.hljs-attr { color: #a6e22e; }
.hljs-string { color: #e6db74; }
.hljs-name { color: #66d9ef; }
.hljs-comment { color: #bbb; }