:root{
  --bg:#F4F4F6;--bg-panel:#FFFFFF;--bg-panel-2:#ECECF1;--border:#DCDCE4;
  --accent:#F4511E;--accent-dark:#C53A0E;--accent-bright:#FF7A4D;--accent-soft:#FDE7DD;
  --text:#15151C;--text-muted:#5C5C6B;--success:#1E9E5A;--warn:#C98A06;--error:#D7263D;
  --blob-orange:#FBC4A8;--blob-pink:#F2C6E6;--blob-sky:#BFE0F7;
  --halo-1:#FDE1D3;--halo-2:#F5D6EC;--halo-3:#D8E8FB;
  --ink-900:#1A1B22;--ink-800:#23242D;--ink-700:#2C2D38;--ink-600:#3B3C4A;
  --ink-text:#EDEDF3;--ink-muted:#9C9DAF;--ink-line:rgba(255,255,255,.07);--ink-hi:rgba(255,255,255,.14);
  --glass:rgba(255,255,255,.72);--glass-strong:rgba(255,255,255,.55);--hi-edge:rgba(255,255,255,.9);
  --shadow-tint:rgba(244,81,30,.12);--shadow-tint-soft:rgba(244,81,30,.10);--shadow-cta:rgba(244,81,30,.30);
  --shadow-ink:rgba(21,21,28,.32);--shadow-deep:rgba(0,0,0,.30);--success-glow:rgba(30,158,90,.26);
  --halo-glow:rgba(245,214,236,.16);--veil:rgba(21,21,28,.42);--clear:transparent;
  --flag-red:#D52B1E;--flag-white:#FFFFFF;--flag-navy:#3C3B6E;--flag-us-red:#B22234;
  --r-xs:4px;--r-sm:6px;--r-md:10px;--r-lg:14px;--r-xl:28px;--r-pill:999px;
  --r-flag:3px;--r-float:12px;--r-icon:8px;--r-row:7px;--r-route:9px;--r-circle:50%;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei","Apple SD Gothic Neo","Malgun Gothic",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei","Apple SD Gothic Neo","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --fs-10:10.5px;--fs-11:11px;--fs-115:11.5px;--fs-12:12px;--fs-125:12.5px;
  --fs-13:13px;--fs-135:13.5px;--fs-14:14px;--fs-15:15px;--fs-16:16px;
  --fs-17:17px;--fs-18:18px;--fs-20:20px;--fs-24:24px;--fs-32:32px;
  --fs-h1:clamp(52px,5.4vw,66px);--fs-h1-mobile:clamp(28px,8vw,40px);
  --fs-h2:clamp(28px,3.6vw,42px);--fs-h3:24px;--weight-display:900;
  --tracking-display:-.03em;--tracking-tight:-.02em;--tracking-short:-.01em;
  --tracking-mono:.04em;--tracking-label:.06em;--tracking-chrome:.02em;
  --gutter:32px;--page-width:1200px;--reading-width:820px;
  --anchor-offset:80px;--toc-offset:16px;--toc-landing:96px;
  --panel-shadow:0 18px 48px -12px var(--shadow-tint-soft),inset 0 1px 0 var(--hi-edge);
  --focus-ring:2px solid var(--accent-dark);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
html,body{margin:0}
body{background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--fs-16);line-height:1.5;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
html.nav-open{overflow:hidden}
a{color:inherit}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:var(--focus-ring);outline-offset:3px;border-radius:var(--r-xs)}
[hidden]{display:none!important}
img{max-width:100%;height:auto}
svg{flex-shrink:0}
ul{margin:0;padding:0;list-style:none}
h1,h2,h3{font-family:var(--font-display);text-wrap:balance}
h1{font-size:var(--fs-h1);font-weight:var(--weight-display);line-height:1.12;letter-spacing:var(--tracking-tight)}
h2{font-size:var(--fs-h2);font-weight:var(--weight-display);line-height:1.2;letter-spacing:var(--tracking-tight);margin:0 0 20px}
h3{font-size:var(--fs-h3);line-height:1.3;margin:0 0 16px}
p{margin:0 0 20px}
code{font-family:var(--font-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--ink-900);color:var(--ink-text);border-radius:var(--r-md)}
pre code{overflow-wrap:normal;white-space:pre}
:where(.grid,.footer-grid,.feature-pair,.cols,.facts)>*{min-width:0}
.no-break{white-space:nowrap}
.wrap{max-width:var(--page-width);margin:0 auto;padding-inline:var(--gutter)}
.reading-wrap{max-width:var(--reading-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:64px;padding-bottom:64px}
.panel,.card{background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--panel-shadow);padding:28px;min-width:0}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.text-link{display:inline-flex;align-items:center;gap:8px;min-height:24px;color:var(--accent-dark);font-weight:700;text-underline-offset:4px}
.reveal{transition:opacity .5s ease,transform .5s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-width:0;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:32px}
.decorated{position:relative;overflow-x:clip;max-width:100%}
.notice{background:var(--bg-panel-2);border-bottom:1px solid var(--border);font-size:var(--fs-13);color:var(--text-muted)}
.notice .wrap{display:flex;align-items:center;gap:10px;height:36px}
.notice-dot{width:8px;height:8px;flex:none;border-radius:var(--r-circle);background:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}
.notice-link{display:inline-flex;align-items:center;gap:6px;min-height:24px;color:var(--text);font-weight:500;text-decoration:underline;text-decoration-color:var(--accent);text-decoration-thickness:1.5px;text-underline-offset:3px}
.notice-link svg{width:14px;height:14px;flex:none}
.notice-link:hover{color:var(--accent-dark)}
#site-header{position:relative;z-index:20}
.masthead{position:relative;background:var(--bg-panel);border-bottom:1px solid var(--border);z-index:21}
.masthead .wrap{position:relative;display:flex;align-items:center;gap:28px;height:64px}
.brand{display:inline-flex;align-items:center;gap:10px;flex:none;text-decoration:none;color:var(--text);font-family:var(--font-display);font-weight:var(--weight-display);font-size:var(--fs-20);letter-spacing:var(--tracking-tight)}
.brand img{width:32px;height:32px;display:block}
.nav{flex:1;display:flex;justify-content:center}
.nav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;flex-wrap:nowrap}
.nav li{display:flex;align-items:center;white-space:nowrap}
.nav li+li::before{content:"·";margin:0 12px;color:var(--text-muted);opacity:.45;font-weight:700}
.nav a{text-decoration:none;font-size:var(--fs-14);color:var(--text-muted);min-height:24px;display:inline-flex;align-items:center;transition:color .15s ease}
.nav a:hover{color:var(--text)}
.nav a[aria-current="page"]{color:var(--text);font-weight:600}
.tools{display:flex;align-items:center;gap:10px;flex:none}
.language-control{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;height:34px;padding:0 10px;border:1px solid var(--border);border-radius:var(--r-sm);font-size:var(--fs-13);color:var(--text-muted);text-decoration:none;background:var(--bg-panel);width:auto;white-space:nowrap}
.lang:hover{color:var(--text);border-color:var(--text-muted)}
.language-menu{position:absolute;top:calc(100% + 8px);right:0;min-width:168px;padding:6px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:var(--panel-shadow);z-index:25}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;text-decoration:none;border-radius:var(--r-sm)}
.language-menu a:hover,.language-menu a[aria-current]{background:var(--accent-soft)}
.login{display:inline-flex;align-items:center;justify-content:center;height:34px;padding:0 16px;border-radius:var(--r-sm);background:var(--text);color:var(--bg-panel);font-size:var(--fs-14);font-weight:600;text-decoration:none;white-space:nowrap;transition:background .15s ease}
.login:hover{background:var(--ink-700)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:var(--r-sm);background:var(--bg-panel);color:var(--text);font-size:var(--fs-20)}
.mobile-drawer{display:none;position:absolute;top:64px;left:0;right:0;z-index:24;background:var(--bg-panel);padding:12px var(--gutter) 20px;max-height:calc(100dvh - 100px);overflow-y:auto;overscroll-behavior:contain;border-bottom:1px solid var(--border);box-shadow:var(--panel-shadow)}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:10px 12px;text-decoration:none;border-radius:var(--r-sm)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current]{background:var(--accent-soft);color:var(--text)}
.drawer-languages{border-top:1px solid var(--border);margin-top:12px;padding-top:12px}
.menu-veil{position:fixed;inset:100px 0 0;z-index:19;background:var(--veil);border:0;width:100%}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:46px;padding:0 22px;border-radius:var(--r-sm);font-family:var(--font-body);font-size:var(--fs-15);font-weight:700;text-decoration:none;border:0;flex-shrink:0;white-space:nowrap;transition:background .15s ease,box-shadow .15s ease,color .15s ease}
.btn svg{width:16px;height:16px;flex:none}
.btn-primary{background:var(--accent);color:var(--bg-panel);box-shadow:0 10px 22px -6px var(--shadow-cta),inset 0 1px 0 var(--ink-hi)}
.btn-primary:hover{background:var(--accent-dark)}
.btn-primary:active{background:var(--accent-dark);box-shadow:inset 0 2px 5px var(--shadow-deep)}
.btn-ghost,.btn-secondary{background:var(--glass);color:var(--text);border:1.5px solid var(--text)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--bg-panel)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--bg-panel-2);color:var(--text-muted);border:1px solid var(--border);box-shadow:none;cursor:not-allowed}
.cta-row{display:flex;gap:12px;margin-top:22px;flex-wrap:wrap;justify-content:center}
.badge{display:inline-flex;align-items:center;gap:8px;padding:4px 12px 4px 10px;border-radius:var(--r-pill);background:var(--glass);border:1px solid var(--hi-edge);box-shadow:0 6px 18px var(--shadow-tint-soft);font-family:var(--font-mono);font-size:var(--fs-125);font-weight:500;color:var(--text);max-width:100%;overflow-wrap:anywhere}
.badge-dot{width:8px;height:8px;border-radius:var(--r-circle);background:var(--accent);flex:none}
.site-footer{border-top:1px solid var(--border);background:var(--bg-panel);padding-top:48px;padding-bottom:28px}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr;gap:40px}
.footer-brand p{margin-top:18px;color:var(--text-muted);max-width:340px}
.footer-heading{font-size:var(--fs-16);font-weight:800;margin:0 0 16px}
.footer-links{display:flex;flex-wrap:wrap;gap:6px 16px}
.footer-links a{display:inline-flex;align-items:center;min-height:32px;color:var(--text-muted);font-size:var(--fs-14);text-underline-offset:4px}
.footer-links a:hover{color:var(--accent-dark)}
.footer-bottom{margin-top:32px;padding-top:20px;border-top:1px solid var(--border);display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:16px;font-size:var(--fs-13);color:var(--text-muted)}
.footer-bottom p{margin:0}
.prose{line-height:1.8;overflow-wrap:anywhere;min-width:0}
.prose h2{margin-top:48px}
.prose h3{margin-top:32px}
.prose ul{list-style:disc;padding-left:24px;margin-bottom:24px}
.prose ol{padding-left:24px;margin-bottom:24px}
.prose li+li{margin-top:8px}
@media(max-width:1060px){
  .nav{display:none}
  .masthead .wrap{justify-content:space-between}
  .tools{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .mobile-drawer:not([hidden]){display:block}
}
@media(max-width:768px){
  :root{--gutter:20px}
  h1{font-size:var(--fs-h1-mobile)}
  .footer-grid{grid-template-columns:1fr;gap:28px}
  .section{padding-top:40px;padding-bottom:40px}
  .panel,.card{padding:20px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .notice-lead{display:none}
  .language-control{display:none}
  .tools{margin-left:auto}
  .masthead .wrap{gap:12px}
  .tilt{transform:none!important}
  .decorated{max-width:100%}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition:none!important;animation:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}