:root{--bg:#f7f9fc;--surface:#fff;--ink:#0f1830;--ink-soft:#4a5573;--accent:#2d5bff;--accent-soft:#e7edff;--line:#e6ebf2}
*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--ink);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif;line-height:1.7;-webkit-font-smoothing:antialiased}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
.wrap{max-width:860px;margin:0 auto;padding:0 28px}
header.nav{padding:22px 0;border-bottom:1px solid var(--line);background:rgba(255,255,255,.7);backdrop-filter:saturate(140%) blur(8px);position:sticky;top:0;z-index:10}
header.nav .wrap{max-width:1080px}
.nav-inner{display:flex;align-items:center;justify-content:space-between}
.nav-right{display:flex;align-items:center;gap:14px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;color:var(--ink)}
.brand:hover{text-decoration:none}
.logo{width:28px;height:28px;border-radius:7px;background:linear-gradient(135deg,#2d5bff,#7aa2ff);position:relative;display:inline-block}
.logo::after{content:"";position:absolute;inset:6px;border-radius:3px;background:#fff;opacity:.85}
.brand img.logo{background:transparent;display:block;object-fit:contain}
nav ul{display:flex;gap:26px;list-style:none;margin:0;padding:0;font-size:14px}
nav a{color:var(--ink-soft)}
.lang-select{height:36px;border:1px solid var(--line);border-radius:8px;background:var(--surface);color:var(--ink);font-size:13px;padding:0 10px;cursor:pointer}
.layout{display:grid;grid-template-columns:220px minmax(0,1fr) 220px;gap:48px;max-width:1320px;margin:0 auto;padding:56px 28px 80px}
.docnav,.toc{position:sticky;top:94px;align-self:start;font-size:13.5px;max-height:calc(100vh - 120px);overflow-y:auto}
.docnav h4,.toc h4{font-size:11px;text-transform:uppercase;letter-spacing:.12em;color:var(--ink-soft);margin:0 0 12px;font-weight:600}
.docnav ul,.toc ul{list-style:none;padding:0;margin:0;border-left:1px solid var(--line)}
.docnav a,.toc a{display:block;padding:7px 14px;color:var(--ink-soft);border-left:2px solid transparent;margin-left:-1px;line-height:1.4}
.docnav a:hover,.toc a:hover{color:var(--accent);text-decoration:none}
.docnav a.active,.toc a.active{color:var(--accent);border-left-color:var(--accent);font-weight:600;background:var(--accent-soft)}
.article{min-width:0}
.article h1{margin-top:0}
@media(max-width:1100px){.layout{grid-template-columns:1fr;gap:0;padding:40px 28px 60px}.docnav,.toc{display:none}}
@media(max-width:820px){.nav-inner{flex-wrap:wrap;gap:12px}.nav-right{width:100%;justify-content:space-between}nav ul{gap:14px;flex-wrap:wrap}}
.crumbs{font-size:13px;color:var(--ink-soft);margin:0 0 18px;text-transform:uppercase;letter-spacing:.08em}
.article h1{font-size:38px;line-height:1.2;margin:0 0 18px;letter-spacing:-.4px}
.article h2{font-size:22px;margin:44px 0 12px;letter-spacing:-.2px}
.article h3{font-size:17px;margin:28px 0 8px}
.article .lead{font-size:18px;color:var(--ink-soft);margin:0 0 8px}
.article p,.article li{color:var(--ink-soft);font-size:15.5px}
.article ul{padding-left:22px}
.article code{font-family:"SF Mono",Menlo,Consolas,monospace;background:var(--accent-soft);color:var(--ink);padding:1px 6px;border-radius:4px;font-size:13.5px}
.article pre{background:#0f1830;color:#e7edff;padding:18px 20px;border-radius:12px;overflow:auto;font-size:13.5px;line-height:1.55}
.article pre code{background:transparent;color:#e7edff;padding:0}
.article table{width:100%;border-collapse:collapse;background:var(--surface);border:1px solid var(--line);border-radius:12px;overflow:hidden;font-size:14px;margin:14px 0}
.article th,.article td{padding:12px 14px;text-align:left;border-bottom:1px solid var(--line)}
.article th{background:#f1f4fa;font-weight:600;color:var(--ink)}
.article tr:last-child td{border-bottom:none}
.share{position:fixed;right:22px;top:50%;transform:translateY(-50%);display:flex;flex-direction:column;gap:10px;z-index:20}
.share a{width:40px;height:40px;border-radius:50%;background:var(--surface);border:1px solid var(--line);display:flex;align-items:center;justify-content:center;color:var(--ink-soft);font-size:15px;font-weight:700;transition:all .2s;box-shadow:0 2px 8px rgba(15,24,48,.04)}
.share a:hover{background:var(--accent);color:#fff;border-color:var(--accent);text-decoration:none;transform:scale(1.08)}
@media(max-width:1180px){.share{display:none}}
.related{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:18px 26px;list-style:none;margin:32px 0 0}
.related li{margin:6px 0;font-size:15px}
footer{padding:42px 0;border-top:1px solid var(--line);color:var(--ink-soft);font-size:13.5px;text-align:center;margin-top:40px}
footer a{color:var(--ink-soft)}