:root {
  --vp-c-brand-1: #0891b2;
  --vp-c-brand-2: #06b6d4;
  --vp-c-brand-3: #22d3ee;
  --vp-c-bg: #fafbfc;
  --vp-c-bg-alt: #f1f5f9;
  --vp-c-bg-soft: #f8fafc;
  --vp-c-text-1: #0f172a;
  --vp-c-text-2: #475569;
  --vp-c-text-3: #94a3b8;
  --vp-c-border: #e2e8f0;
  --vp-c-divider: #e2e8f0;
  --vp-shadow-1: 0 1px 2px rgba(0, 0, 0, 0.04), 0 1px 2px rgba(0, 0, 0, 0.06);
  --vp-shadow-2: 0 3px 12px rgba(0, 0, 0, 0.07), 0 1px 4px rgba(0, 0, 0, 0.07);
  --nav-height: 64px;
  --sidebar-width: 272px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu,
    "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

html.dark {
  --vp-c-brand-1: #22d3ee;
  --vp-c-brand-2: #06b6d4;
  --vp-c-brand-3: #67e8f9;
  --vp-c-bg: #070b14;
  --vp-c-bg-alt: #0f172a;
  --vp-c-bg-soft: #131b2e;
  --vp-c-text-1: #e2e8f0;
  --vp-c-text-2: #94a3b8;
  --vp-c-text-3: #64748b;
  --vp-c-border: #1e293b;
  --vp-c-divider: #1e293b;
  --vp-shadow-1: 0 1px 2px rgba(0, 0, 0, 0.24);
  --vp-shadow-2: 0 3px 12px rgba(0, 0, 0, 0.32);
}

*, *::before, *::after { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--vp-c-bg);
  color: var(--vp-c-text-1);
  font: 16px/1.6 var(--font);
  transition: background 0.25s, color 0.25s;
  overflow-x: hidden;
}

a { color: var(--vp-c-brand-1); text-decoration: none; }
a:hover { color: var(--vp-c-brand-3); }

/* ===== 顶部导航 ===== */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--nav-height);
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--vp-c-divider);
  transition: background 0.25s;
}

html.dark .site-nav {
  background: rgba(27, 27, 31, 0.85);
}

.site-nav .inner {
  max-width: 1280px;
  height: 100%;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  gap: 16px;
}

.site-nav .brand {
  font-size: 18px;
  font-weight: 600;
  color: var(--vp-c-text-1);
  white-space: nowrap;
  margin-right: 8px;
}

.site-nav .brand:hover { color: var(--vp-c-brand-1); }

.site-nav .menu {
  display: flex;
  align-items: center;
  gap: 4px;
  flex: 1;
  overflow-x: auto;
}

.site-nav .menu a {
  padding: 4px 12px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
  color: var(--vp-c-text-2);
  white-space: nowrap;
  transition: color 0.2s, background 0.2s;
}

.site-nav .menu a:hover,
.site-nav .menu a.active {
  color: var(--vp-c-brand-1);
}

.site-nav .menu a.active {
  font-weight: 600;
}

.site-nav .actions {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
}

.social-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.social-link {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 8px;
  color: var(--vp-c-text-2);
  transition: color 0.2s, background 0.2s;
}

.social-link:hover {
  color: var(--vp-c-brand-1);
  background: var(--vp-c-bg-soft);
}

.social-link--text {
  width: auto;
  padding: 0 10px;
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
}

.theme-toggle {
  width: 36px;
  height: 36px;
  border: none;
  border-radius: 8px;
  background: transparent;
  color: var(--vp-c-text-2);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  transition: background 0.2s;
}

.theme-toggle:hover {
  background: var(--vp-c-bg-soft);
}

/* 移动端汉堡菜单 */
.nav-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 8px;
  background: transparent;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-left: auto;
}

.nav-toggle-bar,
.nav-toggle-bar::before,
.nav-toggle-bar::after {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--vp-c-text-1);
  border-radius: 1px;
  transition: transform 0.2s, opacity 0.2s;
}

.nav-toggle-bar {
  position: relative;
}

.nav-toggle-bar::before,
.nav-toggle-bar::after {
  content: "";
  position: absolute;
  left: 0;
}

.nav-toggle-bar::before { top: -6px; }
.nav-toggle-bar::after { top: 6px; }

body.nav-open .nav-toggle-bar { background: transparent; }
body.nav-open .nav-toggle-bar::before { transform: translateY(6px) rotate(45deg); }
body.nav-open .nav-toggle-bar::after { transform: translateY(-6px) rotate(-45deg); }

.nav-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 90;
  background: rgba(15, 23, 42, 0.45);
  backdrop-filter: blur(2px);
}

body.nav-open .nav-backdrop {
  display: block;
}

body.nav-open { overflow: hidden; }

/* ===== 文档页布局（侧栏 + 内容） ===== */
.doc-layout {
  max-width: 1280px;
  margin: 0 auto;
  padding: 32px 24px 64px;
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr;
  gap: 32px;
  align-items: start;
}

.sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 24px);
  max-height: calc(100vh - var(--nav-height) - 48px);
  overflow-y: auto;
  padding-right: 8px;
}

.sidebar-group {
  margin-bottom: 24px;
}

.sidebar-group-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--vp-c-text-1);
  margin: 0 0 8px;
  padding: 0 12px;
}

.sidebar-links {
  list-style: none;
  margin: 0;
  padding: 0;
}

.sidebar-links a {
  display: block;
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 14px;
  color: var(--vp-c-text-2);
  line-height: 1.5;
  transition: color 0.15s, background 0.15s;
}

.sidebar-links a:hover,
.sidebar-links a.active {
  color: var(--vp-c-brand-1);
  background: var(--vp-c-bg-soft);
}

.doc-main h1 {
  margin: 0 0 8px;
  font-size: 28px;
  line-height: 1.3;
}

.doc-main .lead {
  margin: 0 0 32px;
  color: var(--vp-c-text-2);
  font-size: 16px;
}

.article-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.article-list a {
  display: block;
  padding: 16px 20px;
  border-radius: 10px;
  border: 1px solid var(--vp-c-border);
  background: var(--vp-c-bg-soft);
  color: var(--vp-c-text-1);
  transition: border-color 0.2s, box-shadow 0.2s;
}

.article-list a:hover {
  border-color: var(--vp-c-brand-1);
  box-shadow: var(--vp-shadow-1);
  color: var(--vp-c-brand-1);
}

.article-list .num {
  font-size: 12px;
  font-weight: 600;
  color: var(--vp-c-brand-1);
  margin-bottom: 4px;
}

.article-list .title {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
  word-break: break-word;
}

/* 移动端侧栏折叠 */
.sidebar-toggle {
  display: none;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  padding: 12px 16px;
  margin-bottom: 12px;
  border: 1px solid var(--vp-c-border);
  border-radius: 10px;
  background: var(--vp-c-bg-soft);
  color: var(--vp-c-text-1);
  font: 14px/1.4 var(--font);
  font-weight: 600;
  cursor: pointer;
}

.sidebar-toggle-arrow {
  font-size: 12px;
  color: var(--vp-c-text-3);
  transition: transform 0.2s;
}

.doc-layout.sidebar-open .sidebar-toggle-arrow {
  transform: rotate(180deg);
}

.empty-state {
  padding: 48px 24px;
  text-align: center;
  color: var(--vp-c-text-3);
  border: 1px dashed var(--vp-c-border);
  border-radius: 12px;
}

/* ===== 页脚 ===== */
.site-footer {
  border-top: 1px solid var(--vp-c-divider);
  padding: 32px 24px;
  text-align: center;
}

.site-footer p {
  margin: 4px 0;
  font-size: 14px;
  color: var(--vp-c-text-3);
}

/* ===== 文章页顶栏（嵌入独立 HTML 文章时） ===== */
.article-chrome {
  position: sticky;
  top: 0;
  z-index: 9999;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid #e5e7eb;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  font: 13px/1.4 var(--font);
}

html.dark .article-chrome {
  background: rgba(27, 27, 31, 0.92);
  border-color: #2e2e32;
}

.article-chrome a {
  color: #3451b2;
  font-weight: 500;
}

.article-chrome .sep {
  color: #9ca3af;
}

/* ===== 响应式 ===== */
@media (max-width: 960px) {
  .site-nav .inner {
    padding: 0 16px;
    gap: 8px;
  }

  .site-nav .brand {
    font-size: 16px;
    max-width: 42vw;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .doc-layout {
    grid-template-columns: 1fr;
    padding: 20px 16px 48px;
    gap: 0;
  }

  .doc-main h1 {
    font-size: 24px;
  }

  .doc-main .lead {
    font-size: 15px;
    margin-bottom: 20px;
  }

  .article-list a {
    padding: 14px 16px;
  }

  .article-list .title {
    font-size: 15px;
  }

  /* 概览页：主区域已有文章列表，隐藏重复侧栏 */
  .doc-layout--overview .sidebar,
  .doc-layout--overview .sidebar-toggle {
    display: none !important;
  }

  /* 非概览页（如仅侧栏导航）：折叠侧栏 */
  .doc-layout:not(.doc-layout--overview) .sidebar-toggle {
    display: flex;
    grid-column: 1;
  }

  .doc-layout:not(.doc-layout--overview) .sidebar {
    display: none;
    position: static;
    max-height: 45vh;
    overflow-y: auto;
    margin-bottom: 16px;
    padding: 12px;
    border: 1px solid var(--vp-c-divider);
    border-radius: 10px;
    background: var(--vp-c-bg-soft);
  }

  .doc-layout:not(.doc-layout--overview).sidebar-open .sidebar {
    display: block;
  }
}

@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav .brand {
    flex: 1;
    margin-right: 0;
  }

  .site-nav .menu {
    display: none;
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    z-index: 95;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    max-height: calc(100vh - var(--nav-height));
    overflow-y: auto;
    padding: 12px 16px 20px;
    background: var(--vp-c-bg);
    border-bottom: 1px solid var(--vp-c-divider);
    box-shadow: var(--vp-shadow-2);
  }

  body.nav-open .site-nav .menu {
    display: flex;
  }

  .site-nav .menu a {
    padding: 12px 14px;
    font-size: 15px;
    border-radius: 8px;
  }

  .site-nav .actions {
    margin-left: 0;
  }

  .social-link--text {
    padding: 0 8px;
    font-size: 12px;
  }
}