:root {
  color-scheme: light;
  --bg: #f6f7f9;
  --panel: #ffffff;
  --panel-soft: #eef4f7;
  --text: #1c2430;
  --muted: #667085;
  --line: #d8dee8;
  --accent: #0f766e;
  --accent-strong: #115e59;
  --accent-soft: #d9f3ef;
  --code-bg: #111827;
  --code-text: #e5eef8;
  --warn-bg: #fff7e6;
  --warn-line: #f5b84b;
  --shadow: 0 20px 50px rgba(29, 40, 56, 0.10);
}

:root.dark {
  color-scheme: dark;
  --bg: #111418;
  --panel: #191e24;
  --panel-soft: #202934;
  --text: #e6edf3;
  --muted: #9ca9b6;
  --line: #33404e;
  --accent: #5eead4;
  --accent-strong: #2dd4bf;
  --accent-soft: #113b38;
  --code-bg: #080b10;
  --code-text: #e5eef8;
  --warn-bg: #332713;
  --warn-line: #f0b84a;
  --shadow: 0 20px 50px rgba(0, 0, 0, 0.35);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, "Segoe UI", "Microsoft YaHei", Arial, sans-serif;
  line-height: 1.65;
}
button, input { font: inherit; }
.app-shell { display: grid; grid-template-columns: 320px minmax(0, 1fr); min-height: 100vh; }
.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  overflow: auto;
  padding: 24px 20px;
  background: var(--panel);
  border-right: 1px solid var(--line);
}
.brand-block { display: flex; gap: 14px; align-items: center; padding-bottom: 18px; border-bottom: 1px solid var(--line); }
.brand-mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 8px;
  background: var(--accent-soft);
  color: var(--accent-strong);
  font-weight: 800;
}
.eyebrow { margin: 0 0 4px; color: var(--accent-strong); font-size: 12px; font-weight: 800; letter-spacing: 0; text-transform: uppercase; }
.brand-block h1 { margin: 0; font-size: 18px; line-height: 1.25; }
.sidebar-tools { padding: 18px 0; }
.search-label { display: block; margin-bottom: 8px; color: var(--muted); font-size: 13px; font-weight: 700; }
#doc-search {
  width: 100%;
  min-height: 42px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg);
  color: var(--text);
  outline: none;
}
#doc-search:focus { border-color: var(--accent); box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 20%, transparent); }
.search-status { min-height: 20px; margin: 8px 0 0; color: var(--muted); font-size: 12px; }
.toc { display: flex; flex-direction: column; gap: 2px; padding-top: 6px; }
.toc a { display: block; padding: 8px 10px; border-radius: 7px; color: var(--muted); text-decoration: none; font-size: 14px; line-height: 1.35; }
.toc a:hover, .toc a.active { background: var(--accent-soft); color: var(--accent-strong); }
.toc a.level-3 { padding-left: 24px; font-size: 13px; }
.main-panel { min-width: 0; padding: 22px clamp(18px, 4vw, 56px) 56px; }
.topbar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 58px;
  padding: 10px 0;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(14px);
}
.topbar-title { display: flex; flex-direction: column; min-width: 0; font-size: 13px; color: var(--muted); }
.topbar-title strong { color: var(--text); font-size: 16px; }
.actions { display: flex; flex-wrap: wrap; justify-content: flex-end; gap: 8px; }
.tool-button, .icon-button { min-height: 38px; border: 1px solid var(--line); border-radius: 8px; background: var(--panel); color: var(--text); cursor: pointer; }
.tool-button { padding: 0 12px; }
.icon-button { width: 40px; }
.tool-button:hover, .icon-button:hover { border-color: var(--accent); color: var(--accent-strong); }
.mobile-only { display: none; }
.hero-panel {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  margin: 14px 0 24px;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: linear-gradient(135deg, var(--panel), var(--panel-soft));
  box-shadow: var(--shadow);
}
.hero-panel h2 { margin: 0 0 10px; font-size: clamp(24px, 3vw, 38px); line-height: 1.15; }
.hero-panel p:last-child { max-width: 760px; margin: 0; color: var(--muted); }
.hero-meta { align-self: flex-start; min-width: 150px; padding: 12px; border: 1px solid var(--line); border-radius: 8px; background: var(--panel); }
.hero-meta span { display: block; color: var(--muted); font-size: 12px; }
.hero-meta strong { display: block; margin-top: 4px; }
.doc-content {
  max-width: 980px;
  margin: 0 auto;
  padding: clamp(18px, 3vw, 36px);
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--panel);
  box-shadow: var(--shadow);
}
.doc-content h1, .doc-content h2, .doc-content h3, .doc-content h4 { line-height: 1.28; scroll-margin-top: 86px; }
.doc-content h1 { margin: 0 0 22px; font-size: clamp(28px, 4vw, 42px); }
.doc-content h2 { margin: 42px 0 14px; padding-top: 18px; border-top: 1px solid var(--line); font-size: 25px; }
.doc-content h3 { margin: 30px 0 12px; font-size: 20px; }
.doc-content h4 { margin: 24px 0 10px; font-size: 17px; }
.doc-content p, .doc-content li { color: var(--text); }
.doc-content p { margin: 12px 0; }
.doc-content ul, .doc-content ol { margin: 10px 0 18px; padding-left: 25px; }
.doc-content li + li { margin-top: 5px; }
.doc-content a { color: var(--accent-strong); text-underline-offset: 3px; }
.doc-content code:not(pre code) { padding: 2px 5px; border-radius: 5px; background: var(--accent-soft); color: var(--accent-strong); font-size: 0.92em; }
.code-block { position: relative; margin: 16px 0 22px; overflow: hidden; border-radius: 8px; background: var(--code-bg); }
.code-block pre { margin: 0; padding: 18px; overflow: auto; color: var(--code-text); font-size: 13px; line-height: 1.55; }
.code-block code { font-family: "Cascadia Code", Consolas, "SFMono-Regular", monospace; }
.copy-code { position: absolute; top: 8px; right: 8px; min-height: 30px; padding: 0 9px; border: 1px solid rgba(255, 255, 255, 0.22); border-radius: 7px; background: rgba(255, 255, 255, 0.10); color: #fff; cursor: pointer; font-size: 12px; }
.copy-code:hover { background: rgba(255, 255, 255, 0.18); }
.doc-content blockquote { margin: 16px 0; padding: 12px 16px; border-left: 4px solid var(--warn-line); background: var(--warn-bg); border-radius: 0 8px 8px 0; }
mark { padding: 0 2px; border-radius: 3px; background: #ffe16a; color: #1f2937; }
.toast { position: fixed; right: 20px; bottom: 20px; z-index: 30; max-width: min(360px, calc(100vw - 40px)); padding: 11px 14px; border-radius: 8px; background: #111827; color: #fff; box-shadow: var(--shadow); opacity: 0; transform: translateY(8px); pointer-events: none; transition: opacity 0.18s ease, transform 0.18s ease; }
.toast.show { opacity: 1; transform: translateY(0); }
@media (max-width: 980px) {
  .app-shell { grid-template-columns: 1fr; }
  .sidebar { position: fixed; inset: 0 auto 0 0; z-index: 20; width: min(330px, 86vw); transform: translateX(-105%); transition: transform 0.22s ease; box-shadow: var(--shadow); }
  body.sidebar-open .sidebar { transform: translateX(0); }
  .mobile-only { display: inline-grid; }
  .hero-panel { flex-direction: column; }
  .topbar { align-items: flex-start; }
}
@media (max-width: 620px) {
  .main-panel { padding: 14px 12px 36px; }
  .topbar { flex-wrap: wrap; }
  .actions { width: 100%; justify-content: flex-start; }
  .tool-button { flex: 1 1 auto; }
  .hero-panel, .doc-content { padding: 18px; }
}
@media print {
  .sidebar, .topbar, .hero-panel, .toast, .copy-code { display: none !important; }
  .app-shell { display: block; }
  .main-panel, .doc-content { max-width: none; padding: 0; border: 0; box-shadow: none; }
  body { background: #fff; color: #111; }
}