:root {
    --github-dark: #24292e;
    --github-purple: #6f42c1;
    --github-blue: #0366d6;
    --github-green: #28a745;
    --text-dark: #24292e;
    --text-light: #586069;
    --bg-light: #f6f8fa;
    --white: #ffffff;
    --border: #e1e4e8;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 12px rgba(0,0,0,0.15);
    --transition: all 0.2s ease;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--bg-light);
}

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

/* 导航栏样式 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--github-dark);
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 64px;
}

.logo {
    font-size: 20px;
    font-weight: 700;
    color: var(--white);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    font-size: 28px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 24px;
}

.nav-link {
    text-decoration: none;
    color: rgba(255,255,255,0.85);
    font-weight: 500;
    font-size: 14px;
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    color: var(--white);
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--white);
}

/* Hero区域 */
.hero {
    margin-top: 64px;
    padding: 80px 0;
    background: linear-gradient(135deg, var(--github-dark) 0%, #2d3339 100%);
    color: var(--white);
    text-align: center;
}

.hero h1 {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 16px;
    animation: fadeInUp 0.6s ease;
}

.hero p {
    font-size: 18px;
    margin-bottom: 32px;
    opacity: 0.9;
    animation: fadeInUp 0.6s ease 0.15s both;
}

.hero-btn {
    display: inline-block;
    padding: 12px 32px;
    background: var(--github-purple);
    color: var(--white);
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    font-size: 14px;
    transition: var(--transition);
    animation: fadeInUp 0.6s ease 0.3s both;
}

.hero-btn:hover {
    background: #5a35a0;
    transform: translateY(-2px);
}

/* 主内容区域 */
.main-content {
    padding: 48px 0;
}

.section-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 32px;
    text-align: center;
    color: var(--text-dark);
}

/* 卡片网格 */
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 24px;
}

.card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: 6px;
    overflow: hidden;
    transition: var(--transition);
    cursor: pointer;
}

.card:hover {
    border-color: var(--github-blue);
    box-shadow: var(--shadow-hover);
    transform: translateY(-4px);
}

.card-image {
    width: 100%;
    height: 180px;
    object-fit: cover;
    background: var(--bg-light);
}

.card-content {
    padding: 20px;
}

.card-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--github-dark);
}

.card-desc {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 16px;
    line-height: 1.6;
}

.card-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    color: var(--text-light);
}

.card-category {
    background: var(--bg-light);
    color: var(--github-purple);
    padding: 4px 12px;
    border-radius: 12px;
    font-weight: 500;
}

/* 页面标题区域 */
.page-header {
    margin-top: 64px;
    padding: 48px 0 32px;
    background: var(--white);
    border-bottom: 1px solid var(--border);
}

.page-title {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-dark);
}

.breadcrumb {
    color: var(--text-light);
    font-size: 14px;
}

.breadcrumb a {
    color: var(--github-blue);
    text-decoration: none;
}

/* 关于我们页面 */
.about-section {
    background: var(--white);
    padding: 48px 0;
}

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

.about-text {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-light);
    margin-bottom: 24px;
}

.contact-info {
    background: var(--bg-light);
    padding: 24px;
    border-radius: 6px;
    border: 1px solid var(--border);
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: 12px;
}

.contact-icon {
    font-size: 20px;
    margin-right: 12px;
    color: var(--github-purple);
}

/* 页脚 */
.footer {
    background: var(--github-dark);
    color: rgba(255,255,255,0.75);
    padding: 48px 0 24px;
    margin-top: 48px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 32px;
    margin-bottom: 24px;
}

.footer-section h3 {
    font-size: 16px;
    margin-bottom: 16px;
    color: var(--white);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 8px;
}

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

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

.footer-bottom {
    text-align: center;
    padding-top: 24px;
    border-top: 1px solid rgba(255,255,255,0.1);
    color: rgba(255,255,255,0.5);
    font-size: 12px;
}

/* 动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: var(--github-dark);
        flex-direction: column;
        padding: 16px 20px;
        gap: 16px;
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero h1 {
        font-size: 28px;
    }
    
    .hero p {
        font-size: 16px;
    }
    
    .card-grid {
        grid-template-columns: 1fr;
    }
}