:root{
  color-scheme:light;
  --bg:#FBFCFB;
  --panel:#FFFFFF;
  --panel-2:#F3F5F4;
  --panel-3:#FAFBFA;
  --panel-mint:#EAF8F1;
  --border:#E4E7E5;
  --border-strong:#D3D8D5;
  --wire:#CDD3D0;
  --dot:#DCE1DE;
  --accent:#36C98A;
  --accent-deep:#25B377;
  --accent-edge:#2BB47A;
  --accent-dark:#178257;
  --text:#161A18;
  --muted:#5F6763;
  --faint:#8C9490;
  --success:#1F9D55;
  --warn:#C98A16;
  --error:#D64545;
  --fl-red:#A3ABA7;
  --fl-blue:#6B736F;
  --fl-white:#FFFFFF;
  --fl-edge:#D6DBD8;
  --route-red:#959D99;
  --route-blue:#575F5B;
  --clear:rgba(255,255,255,0);
  --white-90:rgba(255,255,255,.92);
  --white-55:rgba(255,255,255,.55);
  --ink-04:rgba(22,26,24,.04);
  --ink-06:rgba(22,26,24,.06);
  --ink-12:rgba(22,26,24,.12);
  --veil-color:rgba(22,26,24,.24);
  --grid:rgba(22,26,24,.032);
  --grid-board:rgba(22,26,24,.05);
  --mint-04:rgba(54,201,138,.04);
  --mint-08:rgba(54,201,138,.08);
  --mint-12:rgba(54,201,138,.12);
  --mint-16:rgba(54,201,138,.16);
  --mint-24:rgba(54,201,138,.24);
  --mint-35:rgba(54,201,138,.35);
  --nav-glass:rgba(251,252,251,.84);
  --sh-1:0 1px 2px var(--ink-04);
  --sh-panel:inset 0 1px 0 var(--white-90),0 1px 2px var(--ink-04),0 24px 56px -22px var(--mint-12);
  --sh-win:inset 0 1px 0 var(--white-90),0 1px 0 var(--border),0 4px 10px var(--ink-04),0 34px 70px -20px var(--mint-16);
  --sh-float:inset 0 1px 0 var(--white-90),0 1px 2px var(--ink-06),0 14px 30px -12px var(--mint-24);
  --sh-cta:inset 0 1px 0 var(--white-55),0 1px 2px var(--ink-06),0 10px 22px -10px var(--mint-35);
  --sh-float-cta:0 12px 28px -10px var(--ink-12),0 2px 6px var(--ink-12);
  --radius:10px;
  --radius-sm:6px;
  --radius-xs:5px;
  --radius-ui:7px;
  --radius-art:8px;
  --radius-flag:3px;
  --radius-pill:999px;
  --radius-round:50%;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --size-body:15px;
  --size-small:13px;
  --size-caption:12px;
  --size-h1:clamp(52px,3.75vw,54px);
  --size-h1-mobile:clamp(28px,7.7vw,40px);
  --size-h2:30px;
  --size-h3:17px;
  --weight-normal:400;
  --weight-medium:500;
  --weight-semibold:600;
  --weight-bold:700;
  --leading-body:1.6;
  --leading-title:1.1;
  --tracking-title:-.02em;
  --gutter:24px;
  --wrap-max:1328px;
  --header-height:64px;
  --anchor-space:80px;
  --toc-space:132px;
  --ease:ease;
  --time-fast:.2s;
  --time-reveal:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-padding-top:var(--anchor-space);scroll-behavior:smooth}
body{margin:0;font-family:var(--font-body);font-size:var(--size-body);line-height:var(--leading-body);color:var(--text);background-color:var(--bg);background-image:linear-gradient(var(--grid) 1px,var(--clear) 1px),linear-gradient(90deg,var(--grid) 1px,var(--clear) 1px);background-size:32px 32px;background-position:center top;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0;max-width:100%;vertical-align:middle}
ul{list-style:none;margin:0;padding:0}
h1,h2,h3,h4,p,blockquote,figure{margin:0}
h1,h2,h3,h4{font-family:var(--font-display);overflow-wrap:break-word}
h1{font-size:var(--size-h1);line-height:var(--leading-title);font-weight:var(--weight-bold);letter-spacing:var(--tracking-title)}
h2{font-size:var(--size-h2);line-height:1.25;font-weight:var(--weight-bold);letter-spacing:var(--tracking-title)}
h3{font-size:var(--size-h3);line-height:1.4;font-weight:var(--weight-semibold)}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent-dark);outline-offset:3px}
[hidden]{display:none!important}
.wrap{width:100%;max-width:var(--wrap-max);margin-inline:auto;padding-inline:var(--gutter)}
section,article,main,aside,nav,header,footer,div{min-width:0}
.no-break{white-space:nowrap}
.mono,code,pre{font-family:var(--font-mono)}
.mono{letter-spacing:-.01em;font-variant-numeric:tabular-nums}
code{overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;border:1px solid var(--border);border-radius:var(--radius);background:var(--panel-2);font-size:var(--size-small)}
pre code{overflow-wrap:normal;white-space:pre}
.defs{position:absolute;width:0;height:0;overflow:hidden}
.ico{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round;flex:none}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.sec{padding-top:64px;padding-bottom:64px}
.section-head{margin-bottom:28px;display:flex;justify-content:space-between;align-items:end;gap:24px}
.section-head p{max-width:560px;color:var(--muted)}
.panel,.card{padding:24px;border:1px solid var(--border);border-radius:var(--radius);background:var(--panel);box-shadow:var(--sh-panel)}
.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}
.stack{display:grid;gap:16px}
.muted{color:var(--muted)}
.link{color:var(--accent-dark);text-decoration:underline;text-underline-offset:4px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:42px;padding:9px 18px;border-radius:var(--radius-sm);font-size:14.5px;font-weight:var(--weight-semibold);line-height:1.5;white-space:nowrap;flex-shrink:0;transition:background-color var(--time-fast) var(--ease),border-color var(--time-fast) var(--ease),box-shadow var(--time-fast) var(--ease)}
.btn .ico{width:15px;height:15px}
.btn-primary{color:var(--text);background:linear-gradient(180deg,var(--accent),var(--accent-deep));border:1px solid var(--accent-edge);box-shadow:var(--sh-cta)}
.btn-primary:hover{box-shadow:var(--sh-float)}
.btn-ghost,.btn-secondary{color:var(--text);background:var(--panel);border:1px solid var(--text)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--panel-2)}
.btn:active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);color:var(--muted);border:1px solid var(--border-strong);box-shadow:none}
.btn-small{min-height:34px;padding:6px 12px;font-size:var(--size-small)}
.topzone{position:relative;overflow-x:clip;max-width:100%}
.topzone::before{content:"";position:absolute;inset:0;background:linear-gradient(180deg,var(--mint-04) 0%,var(--clear) 100%);pointer-events:none;z-index:0}
.nav{position:relative;z-index:50;background:var(--nav-glass);border-bottom:1px solid var(--border)}
.nav-inner{display:flex;align-items:center;gap:36px;min-height:var(--header-height);flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;flex:none;min-height:34px}
.brand-mark{display:block;width:28px;height:28px;flex:none}
.brand-en{font-family:var(--font-display);font-weight:var(--weight-bold);font-size:17px;letter-spacing:-.01em;white-space:nowrap}
.brand-zh{font-size:14px;font-weight:var(--weight-medium);color:var(--muted);white-space:nowrap}
.tabs{height:var(--header-height);flex:1;min-width:0;overflow-x:auto;scrollbar-width:thin}
.tabs ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;height:100%;gap:1px;width:max-content}
.tabs li{flex:none;height:100%}
.tabs a{position:relative;display:flex;align-items:center;min-height:44px;height:100%;padding:0 13px;font-size:14px;color:var(--muted);white-space:nowrap}
.tabs a::after{content:"";position:absolute;left:13px;right:13px;bottom:0;height:2px;border-radius:var(--radius-sm);background:var(--border-strong);transform:scaleX(0)}
.tabs a:hover{color:var(--text)}
.tabs a:hover::after{transform:scaleX(1)}
.tabs a[aria-current="page"]{color:var(--text);font-weight:var(--weight-semibold)}
.tabs a[aria-current="page"]::after{background:var(--accent);transform:scaleX(1)}
.nav-tools{margin-left:auto;display:flex;align-items:center;gap:10px;flex-shrink:0}
.lang-menu{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;height:34px;padding:0 10px;border:0;background:none;border-radius:var(--radius-sm);font-size:13.5px;color:var(--muted);cursor:pointer}
.lang span{white-space:nowrap}
.lang:hover{background:var(--panel-2)}
.lang .ico{width:15px;height:15px}
.lang-panel{position:absolute;right:0;top:calc(100% + 10px);z-index:70;min-width:180px;padding:6px;border:1px solid var(--border);border-radius:var(--radius);background:var(--panel);box-shadow:var(--sh-float)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--radius-sm);font-size:14px;white-space:nowrap}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--panel-2);color:var(--accent-dark)}
.login{display:inline-flex;align-items:center;justify-content:center;min-height:34px;padding:0 16px;border-radius:var(--radius-sm);background:var(--panel);border:1px solid var(--border-strong);box-shadow:var(--sh-1);font-size:13.5px;font-weight:var(--weight-semibold);color:var(--text);white-space:nowrap}
.login:hover{border-color:var(--text)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:4px;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:var(--radius-sm);background:var(--panel)}
.menu-line{display:block;width:20px;height:2px;background:currentColor}
.nav-drawer{display:none;position:fixed;inset-inline:0;top:var(--header-height);height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--panel);padding:16px var(--gutter) 32px;z-index:60;border-top:1px solid var(--border)}
.nav-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px;border-bottom:1px solid var(--border);font-size:14px}
.nav-drawer a[aria-current]{color:var(--accent-dark);font-weight:var(--weight-semibold)}
.drawer-languages{margin-top:20px}
.nav-veil{display:none;position:fixed;inset-inline:0;top:var(--header-height);bottom:0;background:var(--veil-color);border:0;z-index:55}
html.nav-open{overflow:hidden}
.site-footer{position:relative;border-top:1px solid var(--border);background:var(--panel-3);padding-top:48px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr;gap:48px}
.footer-brand p{max-width:340px;margin-top:16px;color:var(--muted);font-size:14px}
.footer-heading{font-size:var(--size-small);font-weight:var(--weight-semibold);margin-bottom:12px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 16px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:28px;font-size:var(--size-small);color:var(--muted);overflow-wrap:anywhere}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent-dark)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;margin-top:32px;padding-top:20px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:12px;margin-top:20px;font-size:var(--size-small);color:var(--muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:20px}
.prose{max-width:820px;line-height:1.85;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-block:18px}
.prose h2{margin-top:48px;margin-bottom:20px}
.prose h3{margin-top:28px;margin-bottom:12px}
.prose ul{list-style:disc;padding-left:24px}
.prose ol{padding-left:24px}
.prose a{color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
.prose .btn{color:var(--text);text-decoration:none}
.reveal{transition:opacity var(--time-reveal) var(--ease),transform var(--time-reveal) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:160px;width:100%;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:24px}
.decorated,.stripe-halo{position:relative;overflow-x:clip;max-width:100%}
@media(max-width:1180px){
  .nav-inner{gap:20px}
  .tabs a{padding-inline:10px}
  .tabs a::after{left:10px;right:10px}
}
@media(min-width:769px) and (max-width:1080px){
  .nav-inner{flex-wrap:wrap;padding-top:12px;column-gap:16px;row-gap:4px}
  .tabs{order:3;flex-basis:100%;width:100%;height:44px;scrollbar-width:none}
  .tabs a{height:44px}
}
@media(max-width:768px){
  :root{--gutter:20px}
  h1{font-size:var(--size-h1-mobile)}
  h2{font-size:26px}
  .sec{padding-top:40px;padding-bottom:40px}
  .nav-inner{gap:12px;height:var(--header-height);min-height:var(--header-height);flex-wrap:nowrap}
  .tabs{display:none}
  .nav-tools{margin-left:auto;gap:6px}
  .menu-toggle{display:inline-flex}
  .nav-drawer:not([hidden]),.nav-veil:not([hidden]){display:block}
  .section-head{display:block}
  .section-head p{margin-top:16px}
  .card-grid{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:28px}
  .footer-bottom{align-items:start;flex-direction:column}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,.decorative-tilt{transform:none}
  .decorated,.stripe-halo{max-width:100%;overflow-x:clip}
  .brand{gap:7px}
  .brand-en{font-size:15px}
  .brand-mark{width:25px;height:25px}
  .lang{font-size:11px;padding-inline:5px;gap:3px}
  .lang .ico{width:13px;height:13px}
  .login{font-size:12px;padding-inline:10px}
  .nav-inner{gap:8px}
  .nav-tools{gap:4px;margin-left:auto}
  .panel,.card{padding:20px}
  .prose{width:100%}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms!important;transition-duration:.01ms!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}