:root{
  --bg:#FAFAF8; --surface:#FFFFFF; --ink:#1A1A1A; --ink-2:#2C2C2C; --muted:#8A857C;
  --muted-2:#B0ACA4; --line:#ECE8E1; --line-2:#E0DDD8; --accent:#C0894B; --accent-soft:#F0EBE3;
  --code-bg:#FBFAF7; --maxw:1480px;
  --sans:'Inter','Noto Sans SC',system-ui,sans-serif; --mono:'JetBrains Mono',monospace;
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{font-family:var(--sans);background:var(--bg);color:var(--ink-2);line-height:1.7;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
::selection{background:rgba(192,137,75,.18)}

/* Topbar */
.topbar{position:sticky;top:0;z-index:50;display:flex;align-items:center;gap:24px;height:60px;padding:0 28px;
  background:rgba(250,250,248,.85);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}
.brand{display:flex;align-items:center;gap:11px;font-weight:500;font-size:15px;color:var(--ink);letter-spacing:-.2px;white-space:nowrap}
.brand-mark{width:22px;height:22px;border-radius:3px;background:linear-gradient(135deg,var(--accent),#9c6a31);flex:none;
  box-shadow:inset 0 1px 2px rgba(255,255,255,.3)}
.menu-toggle{display:none;background:none;border:none;font-size:20px;color:var(--muted);cursor:pointer}
.ver{font-family:var(--mono);font-size:11px;color:var(--muted-2);white-space:nowrap}
.search-wrap{position:relative;margin-left:auto;width:360px;max-width:42vw}
#search{width:100%;height:38px;padding:0 14px;border:1px solid var(--line-2);border-radius:3px;background:var(--surface);
  font-family:var(--sans);font-size:13.5px;color:var(--ink-2);outline:none;transition:border-color .2s,box-shadow .2s}
#search:focus{border-color:var(--accent);box-shadow:0 0 0 3px rgba(192,137,75,.1)}
#search::placeholder{color:var(--muted-2)}
#results{position:absolute;top:46px;left:0;right:0;max-height:62vh;overflow:auto;background:var(--surface);
  border:1px solid var(--line-2);border-radius:4px;box-shadow:0 12px 40px rgba(0,0,0,.1);display:none}
#results.open{display:block}
.res-item{display:block;padding:11px 16px;border-bottom:1px solid var(--line)}
.res-item:last-child{border-bottom:none}
.res-item:hover{background:var(--accent-soft)}
.res-q{font-size:13.5px;color:var(--ink);font-weight:500;line-height:1.45}
.res-path{font-size:11px;color:var(--muted-2);margin-top:3px}
.res-empty{padding:18px 16px;color:var(--muted-2);font-size:13px}
.res-more{padding:10px 16px;text-align:center;color:var(--muted-2);font-size:11.5px;background:var(--code-bg)}
mark{background:rgba(192,137,75,.22);color:inherit;border-radius:2px;padding:0 1px}

/* Layout */
.layout{display:grid;grid-template-columns:288px minmax(0,1fr) 232px;max-width:var(--maxw);margin:0 auto;align-items:start}
.side-nav{position:sticky;top:60px;height:calc(100vh - 60px);overflow:auto;padding:28px 16px 60px 28px;border-right:1px solid var(--line)}
.nav-section{margin-bottom:26px}
.nav-sec-title{font-size:11px;letter-spacing:2.5px;text-transform:uppercase;color:var(--muted-2);font-weight:600;padding:0 12px;margin-bottom:10px}
.side-nav ul{list-style:none}
.side-nav li a{display:block;padding:6.5px 12px;border-radius:4px;font-size:13.5px;color:var(--muted);
  border-left:2px solid transparent;transition:all .15s;line-height:1.35}
.side-nav li a:hover{color:var(--ink);background:rgba(0,0,0,.025)}
.side-nav li.active a{color:var(--accent);background:var(--accent-soft);font-weight:500}

/* Content */
.content{padding:42px 56px 96px;min-width:0}
.crumb{font-size:12px;color:var(--muted-2);letter-spacing:.3px;margin-bottom:14px}
.crumb span{margin:0 7px;opacity:.6}
.page-h1{font-size:38px;font-weight:600;letter-spacing:-1px;color:var(--ink);line-height:1.15}
.page-meta{font-family:var(--mono);font-size:12px;color:var(--accent);margin-top:10px;margin-bottom:8px}
.doc{margin-top:24px}
.doc h3{font-size:23px;font-weight:600;letter-spacing:-.4px;color:var(--ink);margin:54px 0 8px;
  padding-top:22px;border-top:1px solid var(--line)}
.doc h4.qa{display:flex;gap:12px;align-items:flex-start;font-size:18px;font-weight:600;color:var(--ink);
  letter-spacing:-.2px;line-height:1.5;margin:34px 0 14px;scroll-margin-top:76px}
.q-mark{flex:none;width:24px;height:24px;border-radius:5px;background:var(--accent);color:#fff;font-family:var(--mono);
  font-size:13px;font-weight:600;display:flex;align-items:center;justify-content:center;margin-top:2px}
.doc h5{font-size:14.5px;font-weight:600;color:var(--ink-2);margin:22px 0 6px;scroll-margin-top:76px}
.doc h6{font-size:13.5px;font-weight:600;color:var(--muted);margin:16px 0 4px;scroll-margin-top:76px}
.doc h3,.doc h5,.doc h6{scroll-margin-top:76px}
.doc p{font-size:15px;color:#3d3a35;margin:11px 0;line-height:1.78}
.doc ul{margin:12px 0 12px 4px;padding-left:0;list-style:none}
.doc ul li{position:relative;padding-left:20px;margin:7px 0;font-size:14.5px;color:#46433d;line-height:1.7}
.doc ul li::before{content:"";position:absolute;left:4px;top:11px;width:5px;height:5px;border-radius:50%;background:var(--accent);opacity:.65}
.doc figure{margin:20px 0}
.doc figure img{max-width:100%;height:auto;border:1px solid var(--line);border-radius:6px;background:#fff;display:block}
.anchor{opacity:0;margin-left:8px;color:var(--muted-2);font-weight:400;text-decoration:none;transition:opacity .15s}
.doc h3:hover .anchor,.doc h4:hover .anchor,.doc h5:hover .anchor,.doc h6:hover .anchor{opacity:1}

/* Code */
.code-card{background:var(--surface);border:1px solid var(--line);border-radius:6px;overflow:hidden;margin:16px 0;
  box-shadow:0 4px 24px rgba(0,0,0,.025)}
.code-card-header{display:flex;align-items:center;gap:12px;padding:9px 16px;border-bottom:1px solid var(--line);background:#fcfbf9}
.code-card-header .dots{display:flex;gap:6px}
.code-card-header .dots span{width:9px;height:9px;border-radius:50%;background:#E3DFD7}
.code-card-header .filename{font-family:var(--mono);font-size:11px;color:var(--muted-2)}
.copy-btn{margin-left:auto;background:none;border:1px solid var(--line-2);border-radius:3px;padding:3px 9px;
  font-family:var(--sans);font-size:11px;color:var(--muted);cursor:pointer;transition:all .15s}
.copy-btn:hover{color:var(--ink);border-color:var(--muted-2)}
.code-card-body{margin:0;padding:16px 18px;overflow:auto;font-family:var(--mono);font-size:12.8px;line-height:1.7;color:#41463f}
.code-card-body code{font-family:var(--mono);white-space:pre}

/* prev / next */
.prevnext{display:flex;gap:16px;margin-top:64px;padding-top:28px;border-top:1px solid var(--line)}
.pn{flex:1;border:1px solid var(--line-2);border-radius:6px;padding:14px 18px;transition:all .2s;background:var(--surface)}
.pn:hover{border-color:var(--accent);box-shadow:0 4px 18px rgba(0,0,0,.04)}
.pn span{display:block;font-size:11px;color:var(--muted-2);margin-bottom:4px}
.pn b{font-size:14px;color:var(--ink);font-weight:500}
.pn.next{text-align:right}

/* page toc */
.page-toc{position:sticky;top:60px;max-height:calc(100vh - 60px);overflow:auto;padding:46px 24px 60px 8px}
.toc-title{font-size:11px;letter-spacing:2px;text-transform:uppercase;color:var(--muted-2);font-weight:600;margin-bottom:12px}
.page-toc ul{list-style:none}
.page-toc li a{display:block;font-size:12.5px;color:var(--muted);padding:4px 0;line-height:1.4;border-left:2px solid var(--line);padding-left:12px;transition:all .15s}
.page-toc li a:hover{color:var(--ink)}
.page-toc li.toc-h4 a{padding-left:24px;font-size:12px;color:var(--muted-2)}
.page-toc li a.active{color:var(--accent);border-left-color:var(--accent)}

/* Home */
.home{max-width:1080px;margin:0 auto;padding:0 32px 100px}
.hero{text-align:center;padding:84px 0 56px}
.hero-eyebrow{font-size:12px;letter-spacing:4px;text-transform:uppercase;color:var(--accent);margin-bottom:22px;font-weight:500}
.hero h1{font-size:52px;font-weight:600;letter-spacing:-1.6px;color:var(--ink);line-height:1.1}
.hero p{font-size:16px;color:var(--muted);max-width:620px;margin:20px auto 0;line-height:1.7}
.hero p b{color:var(--accent);font-weight:600}
.hero-stats{display:flex;justify-content:center;gap:56px;margin-top:44px}
.hero-stats div{display:flex;flex-direction:column;gap:4px}
.hero-stats b{font-size:30px;font-weight:600;color:var(--ink);letter-spacing:-.5px;font-family:var(--mono)}
.hero-stats span{font-size:12px;color:var(--muted-2);letter-spacing:.5px}
.home-sec{margin-top:54px}
.home-sec-head{display:flex;align-items:baseline;justify-content:space-between;border-bottom:1px solid var(--line-2);padding-bottom:12px;margin-bottom:22px}
.home-sec-head h2{font-size:22px;font-weight:600;color:var(--ink);letter-spacing:-.4px}
.home-sec-head .count{font-family:var(--mono);font-size:12px;color:var(--muted-2)}
.home-grid{list-style:none;display:grid;grid-template-columns:repeat(2,1fr);gap:12px}
.home-grid li a{display:flex;align-items:center;justify-content:space-between;gap:14px;padding:16px 20px;background:var(--surface);
  border:1px solid var(--line);border-radius:6px;transition:all .18s}
.home-grid li a:hover{border-color:var(--accent);transform:translateY(-1px);box-shadow:0 6px 22px rgba(0,0,0,.05)}
.home-grid li a span{font-size:14.5px;color:var(--ink);font-weight:500;line-height:1.35}
.home-grid li a em{flex:none;font-family:var(--mono);font-style:normal;font-size:12px;color:var(--accent);
  background:var(--accent-soft);padding:2px 9px;border-radius:20px}
.site-foot{margin-top:72px;padding-top:28px;border-top:1px solid var(--line);text-align:center;font-size:12.5px;color:var(--muted-2)}

.nav-scrim{display:none}
@media(max-width:1180px){
  .layout{grid-template-columns:260px minmax(0,1fr)}
  .page-toc{display:none}
  .content{padding:38px 40px 90px}
}
@media(max-width:860px){
  .layout{grid-template-columns:1fr}
  .menu-toggle{display:block}
  .search-wrap{width:auto;flex:1}
  .side-nav{position:fixed;top:60px;left:0;width:280px;background:var(--bg);z-index:40;transform:translateX(-100%);transition:transform .25s;border-right:1px solid var(--line-2)}
  body.nav-open .side-nav{transform:none}
  body.nav-open .nav-scrim{display:block;position:fixed;inset:60px 0 0;background:rgba(0,0,0,.25);z-index:30}
  .content{padding:30px 22px 80px}
  .page-h1{font-size:30px}
  .home-grid{grid-template-columns:1fr}
  .hero h1{font-size:38px}
  .hero-stats{gap:32px;flex-wrap:wrap}
}

/* Codex 中转站 悬浮宣传胶囊 */
.promo-badge{position:fixed;right:22px;bottom:22px;z-index:80;display:flex;align-items:center;gap:8px;
  padding:9px 16px 9px 11px;background:#1A1A1A;color:#FAFAF8;border-radius:26px;font-family:var(--sans);
  font-size:13.5px;font-weight:500;text-decoration:none;box-shadow:0 6px 24px rgba(0,0,0,.18);
  transition:transform .18s,box-shadow .18s;letter-spacing:.2px}
.promo-badge:hover{transform:translateY(-2px);box-shadow:0 12px 32px rgba(0,0,0,.26)}
.promo-badge .promo-dot{width:20px;height:20px;border-radius:6px;flex:none;
  background:linear-gradient(135deg,#C0894B,#9c6a31);display:flex;align-items:center;justify-content:center}
.promo-badge .promo-dot::before{content:"\203A";color:#fff;font-weight:700;font-size:14px;line-height:1}
.promo-badge .promo-sub{color:#C0894B;font-size:11.5px;font-weight:400}
@media(max-width:860px){.promo-badge{right:12px;bottom:12px;padding:8px 13px 8px 9px;font-size:12.5px}
  .promo-badge .promo-sub{display:none}}