:root {
    /* 欧美高级感配色：以深邃的蓝灰色为主调，搭配干净的白色和柔和的灰 */
    --primary-color: #0f172a; /* Slate 900 - 沉稳的深色，用于主按钮、Logo */
    --primary-hover: #334155; /* Slate 700 - 悬停状态 */
    --accent-color: #4f46e5; /* Indigo 600 - 提亮色，用于链接和强调 */
    
    --text-main: #111827; /* Gray 900 - 近乎纯黑，高对比度 */
    --text-secondary: #4b5563; /* Gray 600 - 次级文字 */
    --text-light: #9ca3af; /* Gray 400 - 辅助信息 */
    
    --bg-body: #f9fafb; /* Gray 50 - 极淡的暖灰背景，比纯白更有质感 */
    --bg-card: #ffffff;
    
    --border-color: #e5e7eb; /* Gray 200 */
    
    /* 更柔和、扩散感更强的高级阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.025);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.05), 0 10px 10px -5px rgba(0, 0, 0, 0.02);
}

body {
    font-family: "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.75;
    color: var(--text-main);
    background-color: var(--bg-body);
    margin: 0;
    padding: 0;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
}

/* 导航栏 */
.site-header {
    background: var(--bg-card);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 8px;
}

.site-nav ul {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    gap: 30px;
}

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

.site-nav a:hover, .site-nav a.active {
    color: var(--primary-color);
}

/* Hero 区域 */
.hero {
    background: linear-gradient(135deg, #eff6ff 0%, #ffffff 100%);
    padding: 80px 0;
    text-align: center;
    border-bottom: 1px solid var(--border-color);
}

.hero h1 {
    font-size: 2.5rem;
    margin-bottom: 16px;
    color: var(--text-main);
}

.hero p {
    font-size: 1.2rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 32px;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.2s;
}

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

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

/* 主内容区 */
.main-content {
    padding: 60px 0;
}

/* 独立的文章版块 */
.content-section {
    margin-bottom: 80px; /* 版块之间的间距 */
    scroll-margin-top: 100px; /* 滚动定位时的偏移量，避免被导航栏遮挡 */
}

.section-header {
    text-align: center;
    margin-bottom: 40px;
}

.section-header h2 {
    font-size: 1.8rem;
    margin-bottom: 10px;
}

.section-line {
    width: 60px;
    height: 4px;
    background-color: var(--primary-color);
    margin: 0 auto;
    border-radius: 2px;
}

/* 文章卡片网格 */
.posts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.post-card {
    background: var(--bg-card);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s ease;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
}

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

/* 渐变背景卡片头 */
.post-image {
    height: 200px;
    display: block;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    position: relative;
}

/* 给图片增加一个轻微的渐变遮罩，让它更有质感 */
.post-image::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to bottom, rgba(0,0,0,0) 60%, rgba(0,0,0,0.1) 100%);
}

.post-image:hover::after {
    background: linear-gradient(to bottom, rgba(0,0,0,0) 60%, rgba(0,0,0,0.2) 100%);
}

/* 移除旧的渐变类，因为我们现在用图片了 */
/* .gradient-1 { ... } */


.post-content {
    padding: 24px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.post-meta {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
}

.post-card h3 {
    margin: 0 0 12px;
    font-size: 1.25rem;
    line-height: 1.4;
    color: var(--text-main);
}

.post-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 20px;
    flex: 1;
}

.read-more {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    display: inline-flex;
    align-items: center;
}

.read-more:hover {
    text-decoration: underline;
}

/* 页脚 */
.site-footer {
    background: #0f172a; /* Slate 900 */
    color: #f8fafc;
    padding: 80px 0 40px; /* 增加顶部内边距 */
    margin-top: auto;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start; /* 顶部对齐 */
    flex-wrap: wrap;
    gap: 40px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
    padding-bottom: 40px;
    margin-bottom: 40px;
}

.footer-left h4 {
    margin: 0 0 16px;
    font-size: 1.4rem;
    font-weight: 700;
    color: #fff;
}

.footer-left p {
    color: #94a3b8; /* Slate 400 */
    margin: 0;
    max-width: 300px;
    line-height: 1.6;
}

.footer-right {
    text-align: right;
}

.footer-right p {
    margin: 8px 0;
    color: #64748b; /* Slate 500 */
    font-size: 0.9rem;
}

.footer-right a {
    color: #94a3b8;
    transition: color 0.2s;
}

.footer-right a:hover {
    color: #fff;
}

/* 响应式适配 */
@media (max-width: 768px) {
    .header-inner {
        height: 60px;
    }

    .site-nav {
        display: none; /* 移动端暂且隐藏菜单，简化处理 */
    }
    
    .hero h1 {
        font-size: 2rem;
    }
    
    .footer-content {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-right {
        text-align: center;
    }
}