:root{--bg:#fafafa;--surface:#fff;--border:#e4e4e7;--text:#18181b;--muted:#52525b;--faint:#71717a;--accent:#1d4ed8;--accent-hover:#1e40af}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{background:var(--bg);color:var(--text);margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial,Noto Sans,PingFang SC,Microsoft YaHei,sans-serif;font-size:16px;line-height:1.6}.wrap{max-width:960px;margin:0 auto;padding:0 20px}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}.site-header{background:var(--surface);border-bottom:1px solid var(--border)}.site-header .wrap{flex-wrap:wrap;justify-content:space-between;align-items:center;gap:16px;min-height:56px;padding-top:8px;padding-bottom:8px;display:flex}.brand{letter-spacing:-.01em;color:var(--text);font-size:18px;font-weight:700}.brand:hover{text-decoration:none}.nav{flex-wrap:wrap;align-items:center;gap:18px;display:flex}.nav a{color:var(--muted);font-size:14px}.nav a:hover{color:var(--text);text-decoration:none}.nav a[aria-current=page]{color:var(--text);font-weight:600}.lang-menu{position:relative}.lang-menu>summary{cursor:pointer;color:var(--muted);-webkit-user-select:none;user-select:none;font-size:14px;list-style:none}.lang-menu>summary::-webkit-details-marker{display:none}.lang-menu>summary:after{content:"";vertical-align:middle;border:1.5px solid;border-width:0 1.5px 1.5px 0;margin-left:6px;padding:2.5px;display:inline-block;transform:translateY(-1px)rotate(45deg)}.lang-menu[open]>summary{color:var(--text)}.lang-menu[open]>summary:after{transform:translateY(1px)rotate(-135deg)}.lang-menu ul{z-index:30;background:var(--surface);border:1px solid var(--border);border-radius:8px;min-width:148px;margin:0;padding:6px 0;list-style:none;position:absolute;top:calc(100% + 8px);right:0;box-shadow:0 10px 28px #18181b1a}.lang-menu a{color:var(--muted);white-space:nowrap;padding:8px 14px;font-size:14px;text-decoration:none;display:block}.lang-menu a:hover{color:var(--text);background:var(--bg);text-decoration:none}.lang-menu a[aria-current=true]{color:var(--text);font-weight:600}.site-footer .lang-menu ul{top:auto;bottom:calc(100% + 8px)}.btn{background:var(--accent);color:#fff;border-radius:6px;padding:7px 14px;font-size:14px;font-weight:600;display:inline-block}.nav .btn,.nav .btn:hover{color:#fff}.btn:hover{background:var(--accent-hover);color:#fff;text-decoration:none}.btn-lg{border-radius:8px;padding:11px 22px;font-size:16px}.quiet{color:var(--muted);font-size:15px}main{padding:40px 0 56px}.hero{max-width:720px;padding:24px 0 32px}.hero h1{letter-spacing:-.02em;margin:0 0 16px;font-size:36px;line-height:1.2}.lede{color:var(--muted);margin:0 0 24px;font-size:18px}.actions{flex-wrap:wrap;align-items:center;gap:20px;display:flex}.grid{gap:16px;display:grid}.grid.two{grid-template-columns:repeat(2,minmax(0,1fr))}.card{background:var(--surface);border:1px solid var(--border);border-radius:10px;padding:20px 22px}.card h2{margin:0 0 10px;font-size:17px}.card p,.card li{color:var(--muted);font-size:14.5px}.card p{margin:0}.grid.two>.card:last-child:nth-child(odd){grid-column:1/-1}.card code{border:1px solid var(--border);background:#f4f4f5;border-radius:4px;padding:1px 5px;font-size:.9em}.card ul{margin:0;padding-left:18px}.card li{margin:6px 0}.prose{max-width:720px}.prose h1{letter-spacing:-.02em;margin:0 0 16px;font-size:30px}.prose h2{margin:28px 0 8px;font-size:19px}.prose p,.prose li{color:var(--muted);font-size:15.5px}.prose ul{padding-left:20px}.prose li{margin:6px 0}.prose code{border:1px solid var(--border);background:#f4f4f5;border-radius:4px;padding:1px 5px;font-size:.9em}.prose pre{background:var(--surface);border:1px solid var(--border);color:var(--text);border-radius:8px;padding:12px 16px;font-family:ui-monospace,SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:13px;line-height:1.55;overflow-x:auto}.prose pre code{font-size:inherit;background:0 0;border:0;padding:0}.prose h3{margin:22px 0 6px;font-size:16.5px}.prose table{border-collapse:collapse;width:100%;margin:12px 0 20px;font-size:14.5px}.prose th,.prose td{text-align:left;vertical-align:top;border-bottom:1px solid var(--border);color:var(--muted);padding:8px 10px}.prose th{color:var(--text);font-weight:600}.prose.wide{max-width:880px}.spec-links{flex-wrap:wrap;gap:10px 18px;margin:0 0 8px;padding:0;list-style:none;display:flex}.spec-links li{margin:0}.cite{background:var(--surface);border:1px solid var(--border);border-radius:8px;padding:12px 16px;font-family:ui-monospace,SFMono-Regular,Consolas,Liberation Mono,monospace;font-size:14px}.note{color:var(--faint);font-size:14px}.developer-page{padding-top:0}.developer-hero{border-bottom:1px solid var(--border);padding:68px 0 52px}.developer-kicker{color:var(--accent);letter-spacing:.1em;text-transform:uppercase;margin:0 0 10px;font-size:12px;font-weight:750}.developer-hero h1,.spec-header h1{letter-spacing:-.04em;max-width:800px;margin:0 0 18px;font-size:clamp(36px,6vw,52px);line-height:1.12}.developer-lede,.spec-lede{max-width:760px;color:var(--muted);margin:0 0 26px;font-size:18px;line-height:1.75}.developer-lede code{border:1px solid var(--border);background:var(--surface);border-radius:5px;padding:1px 6px;font-size:.9em}.format-facts{border-top:1px solid var(--border);grid-template-columns:repeat(3,minmax(0,1fr));max-width:820px;margin:42px 0 0;padding:20px 0 0;list-style:none;display:grid}.format-facts li{border-left:1px solid var(--border);flex-direction:column;gap:3px;min-width:0;padding:0 24px;display:flex}.format-facts li:first-child{border-left:0;padding-left:0}.format-facts strong{font-size:15px}.format-facts span{color:var(--faint);font-size:13px}.developer-section{border-bottom:1px solid var(--border);padding:56px 0}.developer-section.compact-section{border-bottom:0;padding-bottom:8px}.section-heading{grid-template-columns:minmax(220px,.8fr) minmax(280px,1.2fr);align-items:end;gap:48px;margin-bottom:26px;display:grid}.section-heading h2,.version-heading h2{letter-spacing:-.025em;margin:0;font-size:26px;line-height:1.25}.section-heading>p{color:var(--muted);margin:0;font-size:15px;line-height:1.75}.resource-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:14px;display:grid}.resource-card{border:1px solid var(--border);background:var(--surface);min-height:210px;color:var(--text);border-radius:12px;flex-direction:column;padding:22px;transition:border-color .14s,box-shadow .14s,transform .14s;display:flex}.resource-card:hover{border-color:#1d4ed85c;text-decoration:none;transform:translateY(-1px);box-shadow:0 12px 30px #18181b12}.resource-label{color:var(--accent);letter-spacing:.06em;text-transform:uppercase;margin-bottom:16px;font-size:11px;font-weight:700}.resource-card h3{margin:0 0 8px;font-size:18px}.resource-card p{color:var(--muted);margin:0;font-size:14px;line-height:1.7}.resource-card code{border:1px solid var(--border);background:#f4f4f5;border-radius:4px;padding:1px 4px;font-size:.9em}.resource-link{color:var(--accent);margin-top:auto;padding-top:22px;font-size:13px;font-weight:650}.resource-link:after{content:" →"}.example-list{border:1px solid var(--border);background:#ffffff94;border-radius:9px;margin-top:18px;padding:14px 18px}.example-list summary{cursor:pointer;color:var(--text);font-size:14px;font-weight:650}.example-list div{flex-wrap:wrap;gap:8px 16px;margin-top:12px;display:flex}.example-list a{font-size:13.5px}.workflow-steps{counter-reset:workflow;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px;margin:0;padding:0;list-style:none;display:grid}.workflow-steps li{border:1px solid var(--border);background:var(--surface);counter-increment:workflow;border-radius:12px;min-height:200px;padding:54px 20px 20px;position:relative}.workflow-steps li:before{width:26px;height:26px;color:var(--accent);content:counter(workflow);background:#1d4ed814;border-radius:50%;place-items:center;font-size:12px;font-weight:750;display:grid;position:absolute;top:18px;left:20px}.workflow-steps strong,.workflow-steps span{display:block}.workflow-steps strong{margin-bottom:8px;font-size:15px}.workflow-steps span{color:var(--muted);font-size:13.5px;line-height:1.7}.workflow-steps code,.callout code,.principle-grid code,.version-block code{border:1px solid var(--border);background:#f4f4f5;border-radius:4px;padding:1px 4px;font-size:.9em}.callout{border-left:3px solid var(--accent);color:var(--muted);background:#1d4ed80d;border-radius:0 8px 8px 0;margin:18px 0 0;padding:16px 18px;font-size:14px}.callout strong{color:var(--text)}.principle-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:28px 48px;display:grid}.principle-grid article{border-top:2px solid var(--border);padding-top:16px}.principle-grid h3{margin:0 0 8px;font-size:16px}.principle-grid p{color:var(--muted);margin:0;font-size:14px;line-height:1.75}.version-block{background:linear-gradient(135deg, #1d4ed80f, var(--surface) 58%);border:1px solid #1d4ed82e;border-radius:14px;padding:28px}.version-heading{justify-content:space-between;align-items:flex-start;gap:32px;display:flex}.version-heading p{color:var(--muted);margin:9px 0 0;font-size:14px}.status-pill{color:var(--accent);vertical-align:1px;background:#1d4ed814;border:1px solid #1d4ed833;border-radius:999px;padding:2px 8px;font-size:11px;font-weight:750;line-height:1.7;display:inline-flex}.version-links{flex-wrap:wrap;justify-content:flex-end;gap:8px 16px;display:flex}.version-links a{font-size:13.5px;font-weight:600}.version-block>p{max-width:760px;color:var(--muted);margin:24px 0 0;font-size:14px;line-height:1.75}.spec-header{padding:58px 0 34px}.spec-header h1{max-width:880px;margin-bottom:14px;font-size:clamp(32px,5vw,44px)}.spec-meta{color:var(--faint);flex-wrap:wrap;align-items:center;gap:8px 16px;margin:0 0 22px;font-size:13px;display:flex}.doc-layout{grid-template-columns:190px minmax(0,1fr);align-items:start;gap:44px;display:grid}.doc-sidebar{border-top:1px solid var(--border);border-bottom:1px solid var(--border);padding:15px 0;position:sticky;top:24px}.doc-toc p{color:var(--text);letter-spacing:.08em;text-transform:uppercase;margin:0 0 8px;font-size:12px;font-weight:750}.doc-toc ol{margin:0;padding:0;list-style:none}.doc-toc li{margin:0}.doc-toc a{color:var(--faint);padding:4px 0;font-size:12.5px;line-height:1.35;display:block}.doc-toc a:hover{color:var(--accent)}.spec-document{min-width:0;max-width:none;padding-bottom:24px}.spec-document>h2:first-child{margin-top:0}.spec-document h2{scroll-margin-top:20px}.release-page{padding-top:0}.release-wrap{max-width:880px}.release-hero{border-bottom:1px solid var(--border);margin:0 -28px 48px;padding:64px 28px 44px;position:relative;overflow:hidden}.release-hero:after{content:"";pointer-events:none;background:radial-gradient(circle,#1d4ed81a,#0000 68%);border-radius:50%;width:320px;height:320px;position:absolute;top:-120px;right:-120px}.release-kicker{color:var(--accent);letter-spacing:.1em;text-transform:uppercase;margin:0 0 10px;font-size:12px;font-weight:700}.release-hero h1{letter-spacing:-.035em;margin:0 0 14px;font-size:clamp(34px,6vw,48px);line-height:1.12}.release-intro{max-width:640px;color:var(--muted);margin:0;font-size:18px;line-height:1.7}.release-timeline{padding:0 0 8px 34px;position:relative}.release-timeline:before{background:linear-gradient(var(--accent), var(--border) 74%, transparent);content:"";width:1px;position:absolute;top:8px;bottom:0;left:7px}.release-entry{position:relative}.release-entry+.release-entry{margin-top:56px}.release-entry:before{border:4px solid var(--bg);background:var(--accent);content:"";border-radius:50%;width:15px;height:15px;position:absolute;top:5px;left:-34px;box-shadow:0 0 0 1px #1d4ed83d}.release-meta{align-items:center;gap:12px;margin-bottom:14px;display:flex}.version-badge{min-height:28px;color:var(--accent);background:#1d4ed812;border:1px solid #1d4ed82e;border-radius:999px;align-items:center;padding:3px 10px;font-size:13px;font-weight:700;display:inline-flex}.release-meta time{color:var(--faint);font-size:13px}.release-panel{border:1px solid var(--border);background:var(--surface);border-radius:14px;padding:30px;box-shadow:0 14px 36px #18181b0d}.release-panel h2{letter-spacing:-.02em;margin:0 0 10px;font-size:24px}.release-summary{max-width:650px;color:var(--muted);margin:0;font-size:16px}.release-panel code{border:1px solid var(--border);background:#f4f4f5;border-radius:4px;padding:1px 5px;font-size:.9em}.release-categories{flex-direction:column;gap:34px;margin-top:32px;display:flex}.release-category{--category-color:var(--accent)}.release-category--improvement{--category-color:#0f766e}.release-category--fix{--category-color:#b45309}.release-category-title{color:var(--category-color);letter-spacing:.08em;text-transform:uppercase;align-items:center;gap:10px;margin:0;font-size:12px;font-weight:750;line-height:1.4;display:flex}.release-category-title:before{background:var(--category-color);content:"";border-radius:2px;width:8px;height:8px;transform:rotate(45deg)}.release-category-title:after{background:linear-gradient(90deg, color-mix(in srgb, var(--category-color) 28%, transparent), transparent);content:"";flex:1;height:1px}.release-list{margin-top:8px}.release-note{border-top:1px solid var(--border);padding:18px 4px 18px 24px;position:relative}.release-note:first-child{border-top:0}.release-note:before{border:1px solid color-mix(in srgb, var(--category-color) 45%, white);background:color-mix(in srgb, var(--category-color) 15%, white);content:"";border-radius:50%;width:6px;height:6px;position:absolute;top:25px;left:3px}.release-note h4{color:var(--text);margin:0 0 6px;font-size:16px;line-height:1.45}.release-note p{max-width:720px;color:var(--muted);margin:0;font-size:14px;line-height:1.75}.site-footer{background:var(--surface);border-top:1px solid var(--border);padding:24px 0 28px}.site-footer .wrap{flex-wrap:wrap;align-items:center;gap:18px;display:flex}.site-footer a{color:var(--muted);font-size:14px}.site-footer a:hover{color:var(--text)}.fine{color:var(--faint);margin:0 0 0 auto;font-size:13px}@media (width<=720px){.grid.two{grid-template-columns:1fr}.hero h1{font-size:28px}.release-hero{margin-bottom:36px;margin-left:-20px;margin-right:-20px;padding:46px 20px 34px}.release-intro{font-size:16px}.release-timeline{padding-left:24px}.release-timeline:before{left:5px}.release-entry:before{width:13px;height:13px;left:-25px}.release-meta{flex-direction:column;align-items:flex-start;gap:6px}.release-panel{padding:22px}.release-categories{gap:28px;margin-top:28px}.release-note{padding-right:0}.developer-hero{padding:46px 0 38px}.developer-hero h1,.spec-header h1{font-size:32px}.developer-lede,.spec-lede{font-size:16px}.format-facts,.resource-grid,.workflow-steps,.principle-grid,.section-heading,.doc-layout{grid-template-columns:1fr}.format-facts{gap:14px}.format-facts li,.format-facts li:first-child{border-bottom:1px solid var(--border);border-left:0;padding:0 0 14px}.format-facts li:last-child{border-bottom:0;padding-bottom:0}.developer-section{padding:42px 0}.section-heading{gap:12px}.resource-card,.workflow-steps li{min-height:0}.principle-grid{gap:20px}.version-heading{flex-direction:column}.version-links{justify-content:flex-start}.spec-header{padding:42px 0 28px}.doc-layout{gap:30px}.doc-sidebar{position:static}.doc-toc ol{columns:2;column-gap:24px}}