:root{color-scheme:light dark;--bg:light-dark(#f8f6f2,#16181a);--ink:light-dark(#231a12,#f4ece2);--muted:light-dark(#695e53,#b3a89d);--line:light-dark(#ded6cb,#41403b);--accent:light-dark(#87501f,#efbe89);--card:light-dark(#fffdf9,#222527)}
:root[data-theme="light"]{color-scheme:light}:root[data-theme="dark"]{color-scheme:dark}
*{box-sizing:border-box}html{scroll-padding-top:24px}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.85 -apple-system,BlinkMacSystemFont,"PingFang SC",system-ui,sans-serif}a{color:var(--accent);text-underline-offset:4px}a:hover{text-decoration-thickness:2px}a:focus-visible,button:focus-visible{outline:3px solid var(--accent);outline-offset:4px}header{max-width:1120px;margin:auto;display:flex;align-items:center;gap:24px;padding:24px}.brand{font-size:24px;font-weight:700;margin-right:auto;text-decoration:none;color:var(--ink)}button{font:inherit;border:1px solid var(--line);color:var(--ink);background:var(--card);border-radius:24px;min-height:44px;padding:6px 16px;cursor:pointer}main{max-width:1120px;margin:auto;padding:48px 24px 80px}h1{font-size:clamp(32px,5vw,52px);line-height:1.2;margin:12px 0 20px}h2{font-size:23px;line-height:1.5;margin:0 0 14px}p{margin:0 0 16px}.eyebrow{font-size:11px;letter-spacing:.16em;color:var(--accent)}.meta{font-size:14px;color:var(--muted)}.notice{margin:28px 0;padding:20px 24px;border:1px solid var(--line);border-left:3px solid var(--accent);background:var(--card);border-radius:12px}.notice p{margin:8px 0 0}.pages{display:flex;flex-wrap:wrap;gap:12px 28px;padding:20px 0;border-bottom:1px solid var(--line);margin-bottom:40px}.pages a{min-height:44px;display:inline-flex;align-items:center}.layout{display:grid;grid-template-columns:220px minmax(0,1fr);gap:48px}.toc{align-self:start;position:sticky;top:24px;display:grid;gap:12px;font-size:14px}.toc a{padding:4px 0}article{min-width:0}article section{padding-bottom:32px;margin-bottom:32px;border-bottom:1px solid var(--line)}article p{max-width:72ch;overflow-wrap:anywhere}.references{display:grid;gap:12px}dl{display:grid;grid-template-columns:170px 1fr;gap:12px}dt{color:var(--muted)}dd{margin:0;overflow-wrap:anywhere}footer{max-width:1120px;margin:auto;padding:28px 24px 40px;border-top:1px solid var(--line);font-size:14px;color:var(--muted)}footer nav{display:flex;flex-wrap:wrap;gap:20px;margin-top:16px}.skip{position:absolute;top:-100px;left:16px;background:var(--card);padding:12px;z-index:10}.skip:focus{top:8px}html[data-lang="en"] .zh,html:not([data-lang="en"]) .en{display:none}html[data-lang="en"] body{line-height:1.75}@media(max-width:700px){main{padding-top:24px}.layout{grid-template-columns:1fr;gap:28px}.toc{position:static;border-bottom:1px solid var(--line);padding-bottom:24px;grid-template-columns:repeat(2,minmax(0,1fr))}header{gap:16px}header>a:not(.brand){font-size:14px}dl{grid-template-columns:1fr;gap:4px}dd{margin-bottom:12px}h2{font-size:21px}}
header select{font:inherit;font-size:13px;color:var(--ink);background:var(--panel,transparent);border:1px solid var(--line);border-radius:12px;padding:9px;max-width:140px;cursor:pointer}header select option{color:#202a34;background:white}