/* ========== 基础样式 ========== */
:root {
    --bg: #ffffff;
    --bg-secondary: #f8f9fa;
    --text: #2c3e50;
    --text-secondary: #6b7280;
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --border: #e5e7eb;
    --shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --radius: 8px;
    --max-width: 860px;
    --transition: 0.2s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.75;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color var(--transition);
}

a:hover {
    color: var(--primary-dark);
}

/* ========== 导航栏 ========== */
.navbar {
    background: var(--bg);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(8px);
    background: rgba(255, 255, 255, 0.95);
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 60px;
}

.logo {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text);
    letter-spacing: -0.5px;
}

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

.nav-links {
    list-style: none;
    display: flex;
    gap: 28px;
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 500;
    position: relative;
}

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

.nav-links a.active::after {
    content: "";
    position: absolute;
    bottom: -4px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary);
    border-radius: 2px;
}

.nav-toggle {
    display: none;
    font-size: 1.3rem;
    cursor: pointer;
    color: var(--text);
}

/* ========== 头部区域 ========== */
.hero {
    padding: 80px 0 60px;
    text-align: center;
}

.hero h1 {
    font-size: 2.4rem;
    font-weight: 800;
    color: var(--text);
    margin-bottom: 12px;
    letter-spacing: -1px;
}

.hero p {
    font-size: 1.15rem;
    color: var(--text-secondary);
    max-width: 480px;
    margin: 0 auto;
}

/* ========== 文章列表 ========== */
.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 32px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--border);
}

.articles-section {
    padding-bottom: 40px;
}

.articles-grid {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.article-card {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    padding: 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: box-shadow var(--transition), transform var(--transition);
    cursor: pointer;
}

.article-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
    border-color: var(--primary);
}

.article-date {
    font-size: 0.85rem;
    color: var(--text-secondary);
    white-space: nowrap;
    padding-top: 3px;
    min-width: 90px;
}

.article-info h3 {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text);
}

.article-info p {
    font-size: 0.93rem;
    color: var(--text-secondary);
    margin-bottom: 10px;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-tags {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.tag {
    display: inline-block;
    padding: 2px 10px;
    background: var(--bg-secondary);
    color: var(--text-secondary);
    font-size: 0.78rem;
    border-radius: 20px;
    border: 1px solid var(--border);
}

/* ========== 文章详情 ========== */
.post-container {
    padding-top: 40px;
    padding-bottom: 60px;
}

.post-header {
    margin-bottom: 40px;
}

.post-header h1 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.post-meta {
    display: flex;
    align-items: center;
    gap: 16px;
    color: var(--text-secondary);
    font-size: 0.9rem;
    flex-wrap: wrap;
}

.post-meta span {
    display: flex;
    align-items: center;
    gap: 4px;
}

.post-body {
    font-size: 1.05rem;
    line-height: 1.9;
}

.post-body h2 {
    font-size: 1.4rem;
    margin: 36px 0 16px;
    font-weight: 700;
}

.post-body h3 {
    font-size: 1.15rem;
    margin: 28px 0 12px;
    font-weight: 600;
}

.post-body p {
    margin-bottom: 16px;
}

.post-body ul,
.post-body ol {
    margin: 0 0 16px 24px;
}

.post-body li {
    margin-bottom: 6px;
}

.post-body pre {
    background: #1e293b;
    color: #e2e8f0;
    padding: 20px 24px;
    border-radius: var(--radius);
    overflow-x: auto;
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 20px;
}

.post-body code {
    background: var(--bg-secondary);
    padding: 2px 6px;
    border-radius: 4px;
    font-size: 0.9em;
    font-family: "SF Mono", "Fira Code", "Fira Mono", monospace;
}

.post-body pre code {
    background: none;
    padding: 0;
}

.post-body blockquote {
    border-left: 4px solid var(--primary);
    padding: 12px 20px;
    margin: 20px 0;
    background: var(--bg-secondary);
    border-radius: 0 var(--radius) var(--radius) 0;
    color: var(--text-secondary);
}

.post-body a {
    text-decoration: underline;
    text-underline-offset: 2px;
}

.post-tags {
    margin-top: 48px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

.post-tags .tag {
    margin-right: 8px;
}

/* ========== 返回按钮 ========== */
.back-nav {
    margin-top: 48px;
}

.btn-back {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--text-secondary);
    font-size: 0.95rem;
    padding: 8px 16px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: all var(--transition);
}

.btn-back:hover {
    color: var(--primary);
    border-color: var(--primary);
}

/* ========== 关于区域 ========== */
.about-section {
    padding: 40px 0 60px;
}

.about-card {
    display: flex;
    align-items: flex-start;
    gap: 28px;
    padding: 32px;
    background: var(--bg-secondary);
    border-radius: var(--radius);
    border: 1px solid var(--border);
}

.about-avatar {
    font-size: 3.5rem;
    color: var(--primary);
}

.about-content h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.about-content p {
    color: var(--text-secondary);
    margin-bottom: 16px;
    max-width: 560px;
}

.social-links {
    display: flex;
    gap: 16px;
}

.social-links a {
    font-size: 1.3rem;
    color: var(--text-secondary);
    transition: color var(--transition);
}

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

/* ========== 页脚 ========== */
.footer {
    border-top: 1px solid var(--border);
    padding: 24px 0;
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.88rem;
}

/* ========== 响应式 ========== */
@media (max-width: 640px) {
    .hero {
        padding: 50px 0 36px;
    }

    .hero h1 {
        font-size: 1.7rem;
    }

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

    .nav-links {
        display: none;
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        background: var(--bg);
        flex-direction: column;
        padding: 16px 20px;
        border-bottom: 1px solid var(--border);
        gap: 12px;
    }

    .nav-links.show {
        display: flex;
    }

    .nav-toggle {
        display: block;
    }

    .article-card {
        flex-direction: column;
        gap: 8px;
    }

    .article-date {
        min-width: auto;
    }

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

    .social-links {
        justify-content: center;
    }

    .post-header h1 {
        font-size: 1.5rem;
    }
}