:root {
  --bg: #f6f8fb;
  --panel: #ffffff;
  --text: #1f2937;
  --muted: #6b7280;
  --line: #e5e7eb;
  --brand: #0d9488;
  --brand-soft: #ccfbf1;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: ui-sans-serif, -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 10% 10%, #ecfeff 0, transparent 30%), var(--bg);
}
.layout {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr) 240px;
  min-height: 100vh;
  gap: 20px;
  max-width: 1480px;
  margin: 0 auto;
  padding: 20px;
}
.sidebar, .toc-wrap {
  position: sticky;
  top: 20px;
  align-self: start;
  max-height: calc(100vh - 40px);
  overflow: auto;
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px;
}
.brand {
  display: block;
  margin-bottom: 12px;
  text-decoration: none;
  font-weight: 700;
  color: #0f766e;
}
.search {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px 10px;
  outline: none;
}
.search:focus { border-color: var(--brand); box-shadow: 0 0 0 3px var(--brand-soft); }
.search-results { margin-top: 8px; }
.result-item {
  display: block;
  text-decoration: none;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px;
  margin-bottom: 6px;
  color: inherit;
  background: #fff;
}
.result-item:hover { border-color: #99f6e4; }
.result-title { font-size: 13px; font-weight: 600; }
.result-desc { font-size: 12px; color: var(--muted); margin-top: 4px; }
.result-empty { font-size: 12px; color: var(--muted); padding: 8px; }
.nav { margin-top: 10px; display: flex; flex-direction: column; gap: 6px; }
.nav-group {
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
}
.nav-group[open] {
  border-color: #d1fae5;
}
.nav-group-title {
  cursor: pointer;
  list-style: none;
  font-size: 13px;
  font-weight: 700;
  color: #0f766e;
  padding: 9px 10px;
}
.nav-group-title::-webkit-details-marker {
  display: none;
}
.nav-group-title::after {
  content: "▾";
  float: right;
  color: #6b7280;
  transform: rotate(-90deg);
  transition: transform .15s ease;
}
.nav-group[open] .nav-group-title::after {
  transform: rotate(0deg);
}
.nav-sublist {
  display: flex;
  flex-direction: column;
  gap: 4px;
  border-top: 1px solid var(--line);
  padding: 8px;
}
.nav-item {
  text-decoration: none;
  color: var(--text);
  font-size: 14px;
  padding: 8px 10px;
  border-radius: 8px;
}
.nav-item:hover { background: #f0fdfa; }
.nav-item.active {
  background: #ecfeff;
  color: #0f766e;
  font-weight: 600;
  border: 1px solid #99f6e4;
}
.main {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 24px 28px;
  min-width: 0;
}
.doc h1 { margin-top: 6px; font-size: 34px; }
.doc h2 { margin-top: 30px; font-size: 24px; border-bottom: 1px solid var(--line); padding-bottom: 8px; }
.doc h3 { margin-top: 22px; font-size: 18px; }
.doc p, .doc li { line-height: 1.8; color: #273344; }
.doc ul, .doc ol { padding-left: 22px; }
.doc code {
  background: #f3f4f6;
  border: 1px solid #e5e7eb;
  border-radius: 6px;
  padding: 1px 6px;
}
.doc pre {
  overflow: auto;
  background: #0f172a;
  color: #e2e8f0;
  border-radius: 12px;
  padding: 14px;
}
.doc pre code { background: transparent; border: 0; color: inherit; padding: 0; }
.doc blockquote {
  margin: 14px 0;
  border-left: 3px solid #99f6e4;
  background: #f0fdfa;
  padding: 8px 12px;
  color: #14532d;
}
.pager {
  margin-top: 26px;
  border-top: 1px solid var(--line);
  padding-top: 16px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
}
.pager-link {
  text-decoration: none;
  color: #0f766e;
  font-weight: 600;
}
.toc-title { font-size: 12px; color: var(--muted); margin-bottom: 8px; }
.toc { display: flex; flex-direction: column; gap: 6px; }
.toc-item { text-decoration: none; color: var(--text); font-size: 13px; }
.toc-2 { padding-left: 10px; }
.toc-3 { padding-left: 20px; color: var(--muted); }
.toc-empty { color: var(--muted); font-size: 12px; }

@media (max-width: 1200px) {
  .layout { grid-template-columns: 260px minmax(0, 1fr); }
  .toc-wrap { display: none; }
}
@media (max-width: 860px) {
  .layout { grid-template-columns: 1fr; padding: 10px; gap: 10px; }
  .sidebar { position: static; max-height: none; }
  .main { padding: 18px; }
  .doc h1 { font-size: 28px; }
}