:root { --ink: #23273c; --muted: #5f6678; --line: #e3e6ee; --blue: #555ce1; }
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: white; font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; font-size: 15px; line-height: 1.8; }
a { color: var(--blue); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, summary:focus-visible { outline: 3px solid var(--blue); outline-offset: 4px; }
.skip-link { position: absolute; top: -60px; left: 16px; padding: 8px 12px; background: white; z-index: 2; }
.skip-link:focus { top: 12px; }
.header { height: 68px; display: flex; align-items: center; justify-content: space-between; gap: 20px; padding: 0 32px; border-bottom: 1px solid var(--line); }
.header-actions { display: flex; align-items: center; gap: 22px; }
.header-actions select { min-height: 36px; padding: 0 9px; border: 1px solid var(--line); border-radius: 4px; background: white; color: var(--ink); font: inherit; font-size: 12px; cursor: pointer; }
.brand { display: inline-flex; align-items: center; gap: 9px; color: var(--ink); font-size: 18px; font-weight: 750; }
.brand img { border-radius: 7px; }
.brand span { margin-left: 8px; padding-left: 17px; border-left: 1px solid var(--line); color: var(--muted); font-size: 14px; font-weight: 550; }
.home-link { color: var(--muted); font-size: 13px; }
.layout { max-width: 1280px; margin: auto; display: grid; grid-template-columns: 260px minmax(0, 1fr); }
.sidebar { align-self: start; position: sticky; top: 0; min-height: calc(100vh - 68px); padding: 38px 24px 40px 32px; border-right: 1px solid var(--line); }
.sidebar-label { margin: 0 0 19px; color: #9096a6; font-size: 12px; font-weight: 700; }
.sidebar nav, .mobile-toc nav { display: grid; gap: 4px; }
.sidebar a, .mobile-toc a { display: block; padding: 6px 11px; border-radius: 4px; color: #555c70; font-size: 13px; }
.sidebar a:hover, .mobile-toc a:hover { color: var(--blue); background: #f3f4fe; text-decoration: none; }
main { min-width: 0; padding: 52px clamp(28px, 7vw, 100px) 36px; }
.markdown-body { max-width: 780px; }
.markdown-body h1 { margin: 0 0 20px; font-size: clamp(32px, 4vw, 44px); line-height: 1.25; letter-spacing: 0; }
.markdown-body h2 { margin: 70px 0 20px; padding-bottom: 11px; border-bottom: 1px solid var(--line); font-size: 27px; line-height: 1.35; }
.markdown-body h3 { margin: 35px 0 12px; font-size: 19px; }
.markdown-body p, .markdown-body ul, .markdown-body ol { margin: 0 0 19px; }
.markdown-body li { padding-left: 4px; margin-bottom: 7px; }
.markdown-body strong { color: #222948; }
.markdown-body blockquote { margin: 24px 0; padding: 13px 19px; border-left: 3px solid var(--blue); background: #f5f6fd; color: #505a73; }
.markdown-body blockquote p { margin: 0; }
.markdown-body img { display: block; width: min(100%, 320px); height: auto; margin: 27px 0 35px; border: 1px solid var(--line); border-radius: 5px; }
.markdown-body hr { border: 0; border-top: 1px solid var(--line); margin: 65px 0 28px; }
.markdown-body a[id] { display: block; position: relative; top: -20px; }
.markdown-body code { padding: 2px 5px; background: #f3f4f7; border-radius: 3px; }
.mobile-toc { display: none; }
footer { max-width: 780px; margin-top: 80px; padding-top: 25px; border-top: 1px solid var(--line); color: var(--muted); font-size: 12px; }
footer a { float: right; margin-left: 20px; }
@media (max-width: 800px) {
  .header { padding: 0 20px; }
  .header-actions { gap: 10px; }
  .home-link { display: none; }
  .layout { display: block; }
  .sidebar { display: none; }
  main { padding: 28px 20px 38px; }
  .mobile-toc { display: block; margin-bottom: 35px; border: 1px solid var(--line); border-radius: 4px; }
  .mobile-toc summary { padding: 10px 14px; cursor: pointer; font-size: 13px; font-weight: 650; }
  .mobile-toc nav { padding: 0 10px 12px; }
  .markdown-body h2 { margin-top: 55px; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }