/* ==========================================================
   个人博客 · 简约清新风格
   设计系统：CSS 变量 + 暗色模式 + 响应式
   ========================================================== */

:root {
  --color-primary: #10b981;
  --color-primary-dark: #059669;
  --color-primary-soft: #d1fae5;
  --color-bg: #fafaf9;
  --color-surface: #ffffff;
  --color-text: #1f2937;
  --color-text-secondary: #6b7280;
  --color-border: #e5e7eb;
  --color-code-bg: #f3f4f6;
  --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.06), 0 4px 12px rgba(0, 0, 0, 0.04);
  --shadow-card-hover: 0 4px 8px rgba(0, 0, 0, 0.08), 0 12px 24px rgba(0, 0, 0, 0.08);
  --radius: 12px;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Cascadia Code", "Liberation Mono",
    Menlo, monospace;
  --content-width: 1080px;
  --article-width: 720px;
}

html[data-theme="dark"] {
  --color-primary: #34d399;
  --color-primary-dark: #10b981;
  --color-primary-soft: rgba(52, 211, 153, 0.15);
  --color-bg: #111827;
  --color-surface: #1f2937;
  --color-text: #f3f4f6;
  --color-text-secondary: #9ca3af;
  --color-border: #374151;
  --color-code-bg: #111827;
  --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.3), 0 4px 12px rgba(0, 0, 0, 0.2);
  --shadow-card-hover: 0 4px 8px rgba(0, 0, 0, 0.4), 0 12px 24px rgba(0, 0, 0, 0.3);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.8;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color 0.3s ease, color 0.3s ease;
  -webkit-font-smoothing: antialiased;
}

a {
  color: var(--color-primary-dark);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

img {
  max-width: 100%;
  display: block;
}

/* ---------- 导航栏 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: color-mix(in srgb, var(--color-surface) 85%, transparent);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-logo .logo-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--color-primary);
  display: inline-block;
}

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

.nav-links a {
  color: var(--color-text-secondary);
  font-size: 15px;
  font-weight: 500;
  padding: 4px 0;
  border-bottom: 2px solid transparent;
}

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

.nav-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.theme-toggle {
  width: 38px;
  height: 38px;
  border: 1px solid var(--color-border);
  border-radius: 50%;
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 17px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.theme-toggle:hover {
  transform: rotate(20deg);
  border-color: var(--color-primary);
}

.nav-burger {
  display: none;
  width: 38px;
  height: 38px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-surface);
  color: var(--color-text);
  font-size: 18px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

/* ---------- Hero ---------- */
.hero {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 80px 24px 56px;
  text-align: center;
}

.hero-avatar {
  width: 88px;
  height: 88px;
  margin: 0 auto 24px;
  border-radius: 50%;
  overflow: hidden;
  border: 3px solid var(--color-primary-soft);
}

.hero h1 {
  font-size: clamp(28px, 5vw, 40px);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.hero h1 .accent {
  color: var(--color-primary);
}

.hero p {
  max-width: 560px;
  margin: 0 auto;
  color: var(--color-text-secondary);
  font-size: 18px;
}

/* ---------- 标签筛选 ---------- */
.tag-filter {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 24px 32px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
}

.tag-btn {
  padding: 6px 18px;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: var(--color-surface);
  color: var(--color-text-secondary);
  font-size: 14px;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.2s ease;
}

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

.tag-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #ffffff;
}

/* ---------- 文章卡片网格 ---------- */
.posts-section {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 24px 80px;
}

.posts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 28px;
}

.post-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.post-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card-hover);
}

.post-card-cover {
  height: 6px;
  background: linear-gradient(90deg, var(--color-primary), #6ee7b7);
}

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

.post-card-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 13px;
  color: var(--color-text-secondary);
  margin-bottom: 12px;
}

.post-card-tag {
  background: var(--color-primary-soft);
  color: var(--color-primary-dark);
  padding: 2px 10px;
  border-radius: 999px;
  font-weight: 500;
}

.post-card h2 {
  font-size: 19px;
  font-weight: 700;
  line-height: 1.5;
  margin-bottom: 10px;
}

.post-card h2 a {
  color: var(--color-text);
}

.post-card h2 a:hover {
  color: var(--color-primary-dark);
}

.post-card-excerpt {
  font-size: 15px;
  color: var(--color-text-secondary);
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.post-card-footer {
  margin-top: 18px;
  font-size: 14px;
  font-weight: 600;
}

.empty-state {
  grid-column: 1 / -1;
  text-align: center;
  color: var(--color-text-secondary);
  padding: 60px 0;
}

/* ---------- 文章详情页 ---------- */
.article {
  max-width: var(--article-width);
  margin: 0 auto;
  padding: 64px 24px 80px;
}

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

.article-header .post-card-meta {
  justify-content: center;
}

.article-header h1 {
  font-size: clamp(26px, 4.5vw, 36px);
  font-weight: 800;
  line-height: 1.4;
  letter-spacing: -0.01em;
  margin-bottom: 16px;
}

.article-content h2 {
  font-size: 24px;
  font-weight: 700;
  margin: 40px 0 16px;
  padding-left: 14px;
  border-left: 4px solid var(--color-primary);
  line-height: 1.5;
}

.article-content h3 {
  font-size: 20px;
  font-weight: 700;
  margin: 32px 0 12px;
}

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

.article-content ul,
.article-content ol {
  margin: 0 0 20px 24px;
}

.article-content li {
  margin-bottom: 8px;
}

.article-content blockquote {
  margin: 24px 0;
  padding: 16px 20px;
  border-left: 4px solid var(--color-primary);
  background: var(--color-primary-soft);
  border-radius: 0 8px 8px 0;
  color: var(--color-text);
}

.article-content code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--color-code-bg);
  padding: 2px 6px;
  border-radius: 4px;
}

.article-content pre {
  background: #1e293b;
  color: #e2e8f0;
  padding: 20px;
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 24px 0;
  line-height: 1.6;
}

.article-content pre code {
  background: none;
  padding: 0;
  font-size: 14px;
  color: inherit;
}

/* 上一篇 / 下一篇 */
.article-pagination {
  max-width: var(--article-width);
  margin: 0 auto;
  padding: 0 24px 80px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.pagination-link {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px 20px;
  transition: border-color 0.2s ease, transform 0.2s ease;
}

.pagination-link:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
}

.pagination-link.next {
  text-align: right;
}

.pagination-link .label {
  font-size: 13px;
  color: var(--color-text-secondary);
  display: block;
  margin-bottom: 4px;
}

.pagination-link .title {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text);
}

.pagination-link:hover .title {
  color: var(--color-primary-dark);
}

/* ---------- 关于页 ---------- */
.about {
  max-width: var(--article-width);
  margin: 0 auto;
  padding: 64px 24px 80px;
}

.about-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 48px 40px;
  text-align: center;
}

.about-card .hero-avatar {
  width: 104px;
  height: 104px;
}

.about-card h1 {
  font-size: 28px;
  font-weight: 800;
  margin-bottom: 8px;
}

.about-card .subtitle {
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.about-bio {
  text-align: left;
  margin-bottom: 32px;
}

.about-bio p {
  margin-bottom: 14px;
  color: var(--color-text);
}

.skills {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: center;
  margin-bottom: 32px;
}

.skill-tag {
  background: var(--color-primary-soft);
  color: var(--color-primary-dark);
  padding: 5px 16px;
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
}

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

.social-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 20px;
  border: 1px solid var(--color-border);
  border-radius: 999px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
  transition: all 0.2s ease;
}

.social-links a:hover {
  border-color: var(--color-primary);
  color: var(--color-primary-dark);
  transform: translateY(-2px);
}

/* ---------- 页脚 ---------- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 32px 24px;
  text-align: center;
  color: var(--color-text-secondary);
  font-size: 14px;
}

.site-footer .heart {
  color: var(--color-primary);
}

/* ---------- 响应式 ---------- */
@media (max-width: 768px) {
  .nav-burger {
    display: flex;
  }

  .nav-links {
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    flex-direction: column;
    gap: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    display: none;
  }

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

  .nav-links li {
    width: 100%;
    text-align: center;
  }

  .nav-links a {
    display: block;
    padding: 14px 0;
    border-bottom: none;
  }

  .hero {
    padding: 56px 24px 40px;
  }

  .article-pagination {
    grid-template-columns: 1fr;
  }

  .about-card {
    padding: 36px 24px;
  }
}