/* Variables */
:root {
    --primary-color: #0366d6;
    --primary-hover: #0056b3;
    --secondary-color: #586069;
    --background: #ffffff;
    --surface: #f6f8fa;
    --border: #e1e4e8;
    --text-primary: #24292e;
    --text-secondary: #586069;
    --text-muted: #6a737d;
    --success: #28a745;
    --warning: #ffc107;
    --border-radius: 8px;
    --shadow: 0 2px 8px rgba(36, 41, 46, 0.08);
    --shadow-hover: 0 4px 16px rgba(36, 41, 46, 0.12);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--background);
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.25;
    margin-bottom: 1rem;
}

.section-title {
    font-size: 2rem;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-primary);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 8px 16px;
    font-size: 14px;
    font-weight: 500;
    text-decoration: none;
    border: 1px solid transparent;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.2s ease;
    white-space: nowrap;
}

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

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

.btn-secondary {
    background: var(--surface);
    color: var(--text-primary);
    border-color: var(--border);
}

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

.btn-github {
    background: var(--text-primary);
    color: white;
    padding: 8px 16px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 500;
    font-size: 14px;
    transition: all 0.2s ease;
}

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

/* Header */
.header {
    background: var(--background);
    border-bottom: 1px solid var(--border);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
}

.nav {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color 0.2s ease;
}

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

/* Hero Section */
.hero {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--surface) 0%, var(--background) 100%);
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 8px 16px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 20px;
    font-size: 14px;
    color: var(--text-secondary);
}

.status-indicator {
    width: 8px;
    height: 8px;
    background: var(--warning);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

/* About Section */
.about {
    padding: 80px 0;
    background: var(--background);
}

.about-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.problem-card {
    text-align: center;
    padding: 2rem;
    background: var(--surface);
    border-radius: var(--border-radius);
    border: 1px solid var(--border);
    transition: all 0.2s ease;
}

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

.problem-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.problem-card h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.problem-card p {
    color: var(--text-secondary);
    font-size: 14px;
}

/* Features Section */
.features {
    padding: 80px 0;
    background: var(--surface);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.feature-card {
    display: flex;
    gap: 1.5rem;
    padding: 2rem;
    background: var(--background);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
    transition: all 0.2s ease;
}

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

.feature-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
}

.feature-content h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.feature-content p {
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 1.5;
}

/* Tech Stack Section */
.tech-stack {
    padding: 80px 0;
    background: var(--background);
}

.tech-categories {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
}

.tech-category {
    text-align: center;
}

.tech-category h3 {
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    font-size: 1.25rem;
}

.tech-list {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.75rem;
}

.tech-badge {
    display: inline-block;
    padding: 6px 12px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 20px;
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.2s ease;
}

.tech-badge:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* Getting Started Section */
.getting-started {
    padding: 80px 0;
    background: var(--surface);
}

.getting-started-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    align-items: start;
}

.code-block {
    background: var(--text-primary);
    border-radius: var(--border-radius);
    overflow: hidden;
}

.code-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    font-size: 14px;
    font-weight: 500;
}

.copy-btn {
    background: rgba(255, 255, 255, 0.1);
    border: none;
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
    transition: background 0.2s ease;
}

.copy-btn:hover {
    background: rgba(255, 255, 255, 0.2);
}

pre {
    margin: 0;
    padding: 1.5rem;
    overflow-x: auto;
}

code {
    color: #e6edf3;
    font-family: 'SF Mono', Monaco, Consolas, monospace;
    font-size: 14px;
    line-height: 1.45;
}

.requirements {
    background: var(--background);
    border: 1px solid var(--border);
    border-radius: var(--border-radius);
    padding: 2rem;
}

.requirements h3 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-size: 1.1rem;
}

.requirements ul {
    list-style: none;
}

.requirements li {
    padding: 0.5rem 0;
    color: var(--text-secondary);
    font-size: 14px;
    position: relative;
    padding-left: 1.5rem;
}

.requirements li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--success);
    font-weight: bold;
}

/* Roadmap Section */
.roadmap {
    padding: 80px 0;
    background: var(--background);
}

.roadmap-list {
    max-width: 800px;
    margin: 0 auto;
}

.roadmap-item {
    display: flex;
    gap: 1.5rem;
    padding: 1.5rem 0;
    border-bottom: 1px solid var(--border);
}

.roadmap-item:last-child {
    border-bottom: none;
}

.roadmap-status {
    font-size: 1.5rem;
    flex-shrink: 0;
}

.roadmap-content h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-size: 1.1rem;
}

.roadmap-content p {
    color: var(--text-secondary);
    font-size: 14px;
}

.roadmap-item.completed .roadmap-content h3 {
    color: var(--success);
}

.roadmap-item.in-progress .roadmap-content h3 {
    color: var(--warning);
}

/* Contributing Section */
.contributing {
    padding: 80px 0;
    background: var(--surface);
    text-align: center;
}

.contributing-content {
    max-width: 600px;
    margin: 0 auto;
}

.contributing-content h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.contributing-content p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    line-height: 1.6;
}

.contributing-buttons {
    display: flex;
    justify-content: center;
    gap: 1rem;
}

/* Footer */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 40px 0 20px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: start;
    margin-bottom: 2rem;
}

.footer-section h3 {
    margin-bottom: 0.5rem;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

.footer-links {
    display: flex;
    gap: 2rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-size: 14px;
    transition: color 0.2s ease;
}

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

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

.footer-bottom p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 14px;
}

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

/* Responsive Design */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }

    .nav {
        gap: 1rem;
    }

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

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .section-title {
        font-size: 1.5rem;
    }

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

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

    .feature-card {
        flex-direction: column;
        text-align: center;
    }

    .tech-categories {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .getting-started-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .contributing-buttons {
        flex-direction: column;
        align-items: center;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 2rem;
    }

    .footer-links {
        justify-content: center;
        flex-wrap: wrap;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero {
        padding: 60px 0;
    }

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

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

    .features, .about, .tech-stack, .getting-started, .roadmap, .contributing {
        padding: 60px 0;
    }

    .problem-card, .feature-card, .requirements {
        padding: 1.5rem;
    }
}