:root{
  --bg:#F8F1E4;
  --bg-panel:#FFFBF4;
  --bg-panel2:#EFE3CD;
  --bg-bar:#E8D8BB;
  --bg-sink:#F5ECDD;
  --chrome-top:#FFFDF9;
  --border:#E2D4BC;
  --border-strong:#CDB994;
  --line:#ECE1CE;
  --accent:#2A4E9E;
  --accent-dark:#1B3670;
  --accent-2:#3A63BC;
  --accent-soft:#E4ECF8;
  --accent-soft-2:#CFDDF2;
  --text:#2A2119;
  --muted:#6E6152;
  --faint:#9A8B76;
  --success:#2F8F5B;
  --success-soft:#DCEFE2;
  --warn:#C98A1A;
  --error:#C2412D;
  --pink:#F1B3BF;
  --pink-soft:#FBE5E9;
  --honey:#F4C66A;
  --honey-soft:#FCEFD1;
  --mist:#A9C6E8;
  --mist-soft:#E5EEF9;
  --on-accent:#FFFFFF;
  --knob:#FFFFFF;
  --hi:rgba(255,255,255,.92);
  --flag-white:#FFFFFF;
  --flag-red:#C8342E;
  --flag-blue:#253F80;
  --flag-navy:#1F2C68;
  --veil:rgba(42,33,25,.3);
  --transparent:transparent;
  --shadow-chip:inset 0 1px 0 var(--hi),0 8px 20px -12px rgba(42,78,158,.18);
  --shadow-panel:inset 0 1px 0 var(--hi),0 50px 100px -38px rgba(42,78,158,.28),0 20px 44px -22px rgba(42,78,158,.10);
  --shadow-float:inset 0 1px 0 var(--hi),0 36px 64px -20px rgba(27,54,112,.34),0 12px 24px -12px rgba(27,54,112,.20);
  --shadow-cta:inset 0 1px 0 rgba(255,255,255,.24),inset 0 -2px 0 rgba(27,54,112,.55),0 16px 32px -14px rgba(42,78,158,.62);
  --shadow-knob:0 1px 3px rgba(42,33,25,.32);
  --shadow-track:inset 0 1px 2px rgba(42,33,25,.22);
  --frame-fill:linear-gradient(180deg,rgba(255,251,244,.94),rgba(239,227,205,.74));
  --sheen:linear-gradient(180deg,rgba(255,255,255,.78),rgba(255,255,255,0));
  --pink-fill:radial-gradient(circle at 32% 28%,var(--pink-soft) 0%,var(--pink) 58%);
  --honey-fill:linear-gradient(200deg,var(--honey-soft) 0%,var(--honey) 46%);
  --mist-fill:linear-gradient(160deg,var(--mist-soft) 0%,var(--mist) 60%);
  --r-xs:6px;
  --r-sm:10px;
  --r-md:14px;
  --r-lg:20px;
  --r-xl:26px;
  --r-band:48px;
  --r-pill:999px;
  --r-search:8px;
  --r-tag:4px;
  --r-phone:30px;
  --r-screen:24px;
  --font-display:Georgia,"Iowan Old Style","Times New Roman","Songti SC","STSong","Noto Serif CJK SC","Source Han Serif SC",serif;
  --font-body:"Inter","Noto Sans SC",-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --grain:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='g'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 .165 0 0 0 0 .129 0 0 0 0 .098 0 0 0 .9 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23g)' opacity='.03'/%3E%3C/svg%3E");
  --wrap:1200px;
  --gutter:24px;
  --header-height:60px;
  --anchor-offset:76px;
  --toc-offset:140px;
  --ease: cubic-bezier(.2,.65,.3,1);
  --duration:.2s;
  --reveal-duration:.35s;
}
*{box-sizing:border-box;margin:0;padding:0}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
html.nav-open{overflow:hidden}
body{font-family:var(--font-body);font-size:15px;line-height:1.6;color:var(--text);background:var(--grain),var(--bg);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;cursor:pointer}
button:disabled{cursor:not-allowed}
a,button,summary{touch-action:manipulation}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
ul{list-style:none}
img{max-width:100%;height:auto}
svg{flex-shrink:0}
[hidden]{display:none!important}
:where(main,article,section,nav,div,li){min-width:0}
.wrap{max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:80px;padding-bottom:80px}
.section-heading{max-width:800px;margin:0 auto 32px;text-align:center}
.section-heading p{margin-top:16px;color:var(--muted);font-size:17px}
h1,h2,h3{font-weight:700;line-height:1.2;text-wrap:balance;overflow-wrap:break-word}
h1{font-family:var(--font-display);font-size:clamp(52px,5vw,68px);letter-spacing:-.02em;line-height:1.1}
h2{font-family:var(--font-display);font-size:clamp(30px,3.5vw,44px);letter-spacing:-.02em}
h3{font-size:21px}
p{overflow-wrap:break-word}
.no-break{white-space:nowrap}
.mono,code,pre{font-family:var(--font-mono)}
code{overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:24px;background:var(--bg-sink);border:1px solid var(--border);border-radius:var(--r-md);line-height:1.7}
pre code{overflow-wrap:normal}
.sr-defs{position:absolute;width:0;height:0;overflow:hidden}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.muted{color:var(--muted)}
.kw{color:var(--accent)}
.ico{fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round;width:20px;height:20px}
.panel,.card{background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--shadow-chip);padding:28px}
.panel{box-shadow:var(--shadow-panel)}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;height:50px;min-width:184px;max-width:100%;padding:0 30px;border-radius:var(--r-md);font-size:16px;font-weight:600;white-space:nowrap;flex-shrink:0;transition:transform var(--duration),background var(--duration)}
.btn svg{width:18px;height:18px}
.btn:hover{transform:translateY(-1px)}
.btn:active,.btn.is-active{transform:translateY(1px)}
.btn-primary{color:var(--on-accent);background:linear-gradient(180deg,var(--accent-2) 0%,var(--accent) 72%);box-shadow:var(--shadow-cta)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--accent-dark)}
.btn-ghost,.btn-secondary{color:var(--text);background:var(--bg-panel);border:1.5px solid var(--border-strong);box-shadow:var(--shadow-chip)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--bg-panel2)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.55;transform:none;pointer-events:none}
.btn-small{height:42px;min-width:0;padding-inline:20px;font-size:14px}
.cta-row{display:flex;justify-content:center;gap:14px;margin-bottom:10px;flex-wrap:wrap}
.topbar{position:relative;z-index:70;background:var(--grain),var(--bg);border-bottom:1px solid var(--border)}
.topbar .wrap{display:flex;align-items:center;height:var(--header-height);gap:20px;flex-wrap:nowrap}
.brand{display:flex;align-items:center;gap:10px;font-size:19px;font-weight:700;letter-spacing:-.01em;white-space:nowrap;flex-shrink:0;min-height:30px}
.brand img{width:30px;height:30px}
.brand-zh{font-weight:400;color:var(--muted)}
.tabs-nav{height:100%;margin-left:12px;flex:1;min-width:0}
.tabs{display:flex;align-items:center;list-style:none;margin:0;padding:0;height:100%;gap:2px}
.tabs li{height:100%}
.tabs a{position:relative;display:flex;align-items:center;height:100%;padding:0 14px;font-size:14.5px;color:var(--muted);white-space:nowrap;transition:color var(--duration)}
.tabs a:hover{color:var(--text)}
.tabs a[aria-current="page"]{color:var(--text);font-weight:600}
.tabs a[aria-current="page"]::after{content:"";position:absolute;left:12px;right:12px;bottom:-1px;height:3px;border-radius:var(--r-xs) var(--r-xs) 0 0;background:var(--accent)}
.top-actions{margin-left:auto;display:flex;align-items:center;gap:10px;flex-shrink:0}
.language{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;width:auto;padding:0 12px;border-radius:var(--r-pill);font-size:13.5px;color:var(--muted);white-space:nowrap}
.lang span{white-space:nowrap}
.lang svg{width:16px;height:16px}
.lang-panel{position:absolute;top:calc(100% + 10px);right:0;z-index:90;width:180px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:var(--shadow-float)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-sm)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--accent-soft);color:var(--accent-dark)}
.login{display:inline-flex;align-items:center;justify-content:center;gap:7px;height:38px;padding:0 18px;border-radius:var(--r-pill);border:1.5px solid var(--text);background:var(--bg-panel);font-size:14px;font-weight:600;box-shadow:var(--shadow-chip);white-space:nowrap;transition:background var(--duration),color var(--duration)}
.login svg{width:16px;height:16px}
.login:hover{background:var(--text);color:var(--bg-panel)}
.burger{display:none;min-width:44px;min-height:44px;align-items:center;justify-content:center;flex-direction:column;gap:4px;border-radius:var(--r-sm)}
.burger-line{display:block;width:20px;height:2px;background:currentColor}
.mobile-drawer{display:none;position:fixed;z-index:65;top:var(--header-height);right:0;left:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--bg-panel);padding:20px var(--gutter)}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;border-radius:var(--r-sm)}
.mobile-drawer a[aria-current]{background:var(--accent-soft);color:var(--accent-dark)}
.drawer-languages{border-top:1px solid var(--border);margin-top:16px;padding-top:16px}
.nav-veil{display:none;position:fixed;inset:var(--header-height) 0 0;z-index:60;background:var(--veil)}
.site-footer{padding-top:64px;padding-bottom:28px;border-top:1px solid var(--border);background:var(--grain),var(--bg-panel2)}
.footer-grid{display:grid;grid-template-columns:1.35fr 1fr 1.2fr .8fr;gap:40px}
.footer-brand p{max-width:300px;margin-top:18px;color:var(--muted)}
.footer-title{font-family:var(--font-body);font-size:14px;margin-bottom:14px}
.footer-links{display:grid;gap:6px}
.footer-links a{display:inline-flex;align-items:center;min-height:28px;font-size:14px;color:var(--muted)}
.footer-links a:hover{color:var(--text);text-decoration:underline;text-underline-offset:4px}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;margin-top:40px;padding-top:24px;border-top:1px solid var(--border);font-size:13px;color:var(--muted)}
.footer-legal{display:flex;gap:20px;flex-wrap:wrap}
.footer-legal a{display:inline-flex;align-items:center;min-height:28px}
.prose{max-width:800px;margin-inline:auto;font-size:16px;line-height:1.9}
.prose p,.prose ul,.prose ol,.prose pre,.prose table{margin-block:20px}
.prose ul{list-style:disc;padding-left:24px}
.prose ol{padding-left:24px}
.prose h2{margin-top:48px;margin-bottom:20px;font-size:32px}
.prose h3{margin-top:32px;margin-bottom:16px}
.prose a{text-decoration:underline;text-underline-offset:4px}
.reveal{transition:opacity var(--reveal-duration) var(--ease),transform var(--reveal-duration) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:120px;max-width:100%;overflow:hidden;margin-block:32px}
#server-status+*{margin-top:32px}
#server-status :where(.grid,[class*="grid"]){min-width:0;max-width:100%}
.decorated{position:relative;overflow-x:clip;max-width:100%}
@media(min-width:1101px) and (max-width:1279px){
  .topbar .wrap{gap:12px}
  .tabs-nav{margin-left:0}
  .tabs a{padding-inline:9px;font-size:13px}
  .top-actions{gap:4px}
}
@media(max-width:1100px){
  .tabs-nav{display:none}
  .top-actions{margin-left:auto}
  .burger{display:flex}
  html.nav-open .mobile-drawer{display:block}
  html.nav-open .nav-veil{display:block}
}
@media(max-width:768px){
  h1{font-size:clamp(28px,7vw,40px)}
  .grid{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px}
  .section{padding-top:56px;padding-bottom:56px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none}
  .decorated{max-width:100%;overflow-x:clip}
  .topbar .wrap{gap:8px}
  .brand{font-size:16px;gap:7px}
  .brand img{width:26px;height:26px}
  .top-actions{gap:2px;margin-left:auto}
  .lang{padding-inline:6px;font-size:11px;gap:3px}
  .lang svg{width:14px;height:14px}
  .login{padding-inline:12px;font-size:13px}
  .login svg{display:none}
  .panel,.card{padding:22px}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .btn{min-width:0;padding-inline:24px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:0s!important;animation-duration:0s!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}