:root {
    --primary-color: #2c3e50;
    --secondary-color: #34495e;
    --accent-color: #3498db;
    --light-bg: #f5f7fa;
    --border-color: #ddd;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    line-height: 1.6;
    background: var(--light-bg);
    padding-top: 80px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    width: 100%;
}

.container {
    max-width: 1440px;
    margin: 0 auto;
    padding: 24px 40px;
    width: 100%;
}

/* 专题头部 */
.topic-header {
    padding: 60px 40px;
    color: white;
    border-radius: 12px;
    margin-bottom: 30px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.topic-title {
    font-size: 2.5em;
    margin-bottom: 20px;
    text-align: center;
}

.topic-description {
    font-size: 1.1em;
    opacity: 0.9;
    max-width: 800px;
    text-align: center;
    margin: 0 auto;
}

/* 文章列表 */
.article-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.article-item {
    margin-bottom: 20px;
}

.article-link {
    text-decoration: none;
    color: inherit;
}

.article-content {
    max-width: 80%;
    margin: 0 auto;
    background: white;
    border-radius: 12px;
    overflow: hidden;
    display: flex;
    transition: transform 0.2s ease;
}

.article-content:hover {
    transform: translateY(-3px);
}

.article-image {
    width: 280px;
    height: 180px;
    flex-shrink: 0;
}

.article-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.article-text {
    padding: 20px;
    flex: 1;
}

.article-text h3 {
    margin: 0 0 10px;
    font-size: 1.3em;
    color: #333;
}

.article-description {
    color: #666;
    margin: 0 0 15px;
    font-size: 0.95em;
    line-height: 1.6;
}

.article-meta {
    color: #999;
    font-size: 0.9em;
    display: flex;
    gap: 15px;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .container {
        padding: 16px;
    }

    .topic-header {
        padding: 40px 20px;
        margin: -16px -16px 20px -16px;
        border-radius: 0;
    }

    .article-content {
        flex-direction: column;
    }

    .article-image {
        width: 100%;
        height: 200px;
    }

    .article-text {
        padding: 15px;
    }

    .article-meta {
        flex-wrap: wrap;
        gap: 10px;
    }
}

/* 深色模式 */
@media (prefers-color-scheme: dark) {
    .article-content {
        background: #1a1a1a;
    }

    .article-text h3 {
        color: #fff;
    }

    .article-description {
        color: #aaa;
    }
}