/* 基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #64748b;
    --text-color: #1e293b;
    --text-light: #64748b;
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --border-color: #e2e8f0;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 40px rgba(0,0,0,0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
}

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

a {
    text-decoration: none;
    color: inherit;
}

/* 导航栏 */
.navbar {
    background: var(--card-bg);
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

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

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    color: var(--text-color);
    transition: color 0.3s;
}

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

/* 主横幅 */
.hero {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-dark));
    color: white;
    padding: 80px 20px;
    text-align: center;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 15px;
}

.hero-subtitle {
    font-size: 1.25rem;
    opacity: 0.9;
    margin-bottom: 30px;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 8px;
    font-weight: 600;
    transition: all 0.3s;
}

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

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

/* 章节标题 */
.section-title {
    font-size: 2rem;
    text-align: center;
    margin: 60px 0 40px;
    color: var(--text-color);
}

/* 文章网格 */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.article-card {
    background: var(--card-bg);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform 0.3s, box-shadow 0.3s;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.article-cover {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.article-cover-placeholder {
    width: 100%;
    height: 200px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 4rem;
}

.article-content {
    padding: 20px;
}

.article-card h3 {
    margin-bottom: 10px;
}

.article-card h3 a {
    color: var(--text-color);
    transition: color 0.3s;
}

.article-card h3 a:hover {
    color: var(--primary-color);
}

.article-summary {
    color: var(--text-light);
    margin-bottom: 15px;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-meta {
    display: flex;
    gap: 15px;
    font-size: 0.875rem;
    color: var(--text-light);
}

/* 分页 */
.pagination {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin: 40px 0;
}

.page-link {
    display: inline-block;
    padding: 10px 15px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: var(--text-color);
    transition: all 0.3s;
}

.page-link:hover,
.page-link.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* 特色服务 */
.features-section {
    background: var(--card-bg);
    padding: 60px 20px;
    margin: 0 -20px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.feature-card {
    text-align: center;
    padding: 30px;
    border-radius: 12px;
    background: var(--bg-color);
    transition: transform 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.feature-card h3 {
    margin-bottom: 10px;
    color: var(--primary-color);
}

.feature-card p {
    color: var(--text-light);
}

/* 文章详情页 */
.article-detail {
    background: var(--card-bg);
    padding: 40px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    margin: 40px auto;
    max-width: 900px;
}

.article-header {
    margin-bottom: 30px;
    padding-bottom: 30px;
    border-bottom: 1px solid var(--border-color);
}

.article-header h1 {
    font-size: 2.5rem;
    margin-bottom: 15px;
    line-height: 1.3;
}

.article-meta {
    display: flex;
    gap: 20px;
    color: var(--text-light);
    flex-wrap: wrap;
}

.article-content {
    font-size: 1.1rem;
    line-height: 1.8;
}

.article-content h2 {
    margin: 30px 0 15px;
    color: var(--primary-color);
    font-size: 1.5rem;
}

.article-content p {
    margin-bottom: 20px;
}

.article-content ul,
.article-content ol {
    margin: 20px 0;
    padding-left: 30px;
}

.article-content li {
    margin-bottom: 10px;
}

.article-content pre {
    background: #1e293b;
    color: #e2e8f0;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 20px 0;
}

.article-content code {
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 0.9rem;
}

.article-footer {
    margin-top: 40px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
}

.tags {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
    align-items: center;
}

.tag {
    background: var(--bg-color);
    padding: 5px 15px;
    border-radius: 20px;
    font-size: 0.875rem;
    color: var(--primary-color);
}

.share-buttons {
    margin-top: 30px;
    display: flex;
    gap: 10px;
    align-items: center;
}

.share-btn {
    padding: 8px 20px;
    border: 1px solid var(--border-color);
    background: white;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s;
}

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

/* 相关文章 */
.related-articles {
    margin: 60px 0;
}

.related-articles h2 {
    font-size: 1.5rem;
    margin-bottom: 30px;
}

/* 页脚 */
.footer {
    background: #1e293b;
    color: #94a3b8;
    padding: 60px 20px 30px;
    margin-top: 60px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    max-width: 1200px;
    margin: 0 auto;
}

.footer-section h4 {
    color: white;
    margin-bottom: 15px;
    font-size: 1.1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 10px;
}

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

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    margin-top: 40px;
    border-top: 1px solid #334155;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .nav-links {
        gap: 15px;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .article-detail {
        padding: 20px;
    }
    
    .article-header h1 {
        font-size: 1.75rem;
    }
}