:root{
  --paper:#FAF4E9;
  --paper-top:#FDF9F1;
  --paper-bottom:#F4EBDA;
  --panel:#FFFDF8;
  --panel-2:#F2EADB;
  --panel-glass:rgba(255,253,248,.72);
  --card-foot:#F7EFE2;
  --line:#E4D8C4;
  --line-soft:rgba(228,216,196,.72);
  --accent:#9B3E8A;
  --accent-hi:#B4589F;
  --accent-press:#8A3479;
  --accent-dark:#74296A;
  --accent-tint:#F4E6F0;
  --accent-tint-soft:rgba(155,62,138,.06);
  --accent-line:rgba(155,62,138,.22);
  --accent-mark:rgba(155,62,138,.18);
  --ink:#2F3A4A;
  --ink-dark:#242D3A;
  --ink-tint:#E8E7E6;
  --text:#2B211A;
  --text-muted:#6E6255;
  --text-faint:#A0927F;
  --white:#FFFFFF;
  --success:#3E8A4F;
  --warn:#C98A14;
  --error:#C2412F;
  --flag-red:#C8372D;
  --flag-blue:#2D4A86;
  --flag-white:#FFFFFF;
  --flag-edge:rgba(43,33,26,.14);
  --grain-ink:rgba(43,33,26,.03);
  --glow-paper:rgba(255,253,248,.9);
  --shadow-tint:rgba(155,62,138,.14);
  --shadow-card:0 16px 40px rgba(155,62,138,.10),0 2px 6px rgba(116,41,106,.05);
  --shadow-card-hover:0 20px 44px rgba(155,62,138,.13),0 3px 8px rgba(116,41,106,.06);
  --shadow-chip:0 8px 22px rgba(155,62,138,.12),0 1px 2px rgba(116,41,106,.08);
  --shadow-soft:0 4px 14px rgba(155,62,138,.07);
  --shadow-btn:0 10px 22px -10px rgba(116,41,106,.55);
  --shadow-btn-ink:0 10px 22px -10px rgba(36,45,58,.5);
  --hl-inset:inset 0 1px 0 rgba(255,255,255,.95),inset 0 0 0 1px rgba(255,255,255,.55);
  --btn-hl:rgba(255,255,255,.22);
  --veil:rgba(43,33,26,.3);
  --radius:8px;
  --radius-mark:6px;
  --radius-pill:999px;
  --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','Yu Gothic','Microsoft YaHei','Apple SD Gothic Neo','Malgun Gothic',system-ui,sans-serif;
  --font-mono:'JetBrains Mono',ui-monospace,'SFMono-Regular',Menlo,Consolas,monospace;
  --weight-normal:400;
  --weight-medium:500;
  --weight-bold:600;
  --display-size:64px;
  --heading-size:32px;
  --subheading-size:22px;
  --body-size:16px;
  --small-size:14px;
  --gutter:24px;
  --wrap-width:1168px;
  --reading-width:832px;
  --header-height:64px;
  --anchor-offset:80px;
  --toc-offset:88px;
  --section-space:64px;
  --space-1:8px;
  --space-2:16px;
  --space-3:24px;
  --space-4:32px;
  --space-5:40px;
  --space-6:48px;
  --motion-fast:.2s;
  --motion-normal:.6s;
}
*,*::before,*::after{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:var(--body-size);font-weight:var(--weight-normal);color:var(--text);background:var(--paper);line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button,a,summary{-webkit-tap-highlight-color:var(--accent-mark)}
button{border:0}
a:focus-visible,button:focus-visible,summary:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible,[tabindex]:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
[hidden]{display:none!important}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0;max-width:100%}
ul{list-style:none}
h1,h2,h3{font-family:var(--font-display);font-weight:var(--weight-normal);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,5vw,var(--display-size));line-height:1.12;letter-spacing:-.02em}
h2{font-size:var(--heading-size);line-height:1.3;letter-spacing:-.02em}
h3{font-size:var(--subheading-size);line-height:1.4}
p{overflow-wrap:break-word}
code{font-family:var(--font-mono);overflow-wrap:anywhere;color:var(--accent-dark)}
pre{max-width:100%;overflow-x:auto;padding:var(--space-3);border:1px solid var(--line);border-radius:var(--radius);background:var(--panel-2)}
pre code{white-space:pre;overflow-wrap:normal;color:var(--text)}
.no-break{white-space:nowrap}
.wrap{width:100%;max-width:var(--wrap-width);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:var(--reading-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.section-head{margin-bottom:var(--space-4)}
.section-head p{margin-top:var(--space-2);color:var(--text-muted);max-width:72ch}
.grid{display:grid;gap:var(--space-3)}
.grid>*{min-width:0}
.grid-three{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-five{grid-template-columns:repeat(5,minmax(0,1fr))}
.panel{padding:var(--space-3);border:1px solid var(--line-soft);border-radius:var(--radius);background:var(--panel);box-shadow:var(--shadow-card),var(--hl-inset)}
.paper-region{position:relative;overflow-x:clip;max-width:100%}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-block:var(--space-3)}
.prose ul{list-style:disc;padding-left:var(--space-3)}
.prose ol{padding-left:var(--space-3)}
.prose li+li{margin-top:var(--space-1)}
.prose h2{margin-top:var(--space-6);margin-bottom:var(--space-2)}
.prose h3{margin-top:var(--space-4);margin-bottom:var(--space-1)}
.prose a{text-decoration:underline;text-underline-offset:4px;color:var(--accent-dark)}
.prose section[id]{scroll-margin-top:var(--anchor-offset)}
body:has(.toc-tabs) section[id],body:has(.toc-tabs) h2[id]{scroll-margin-top:var(--toc-offset)}
.btn{display:inline-flex;align-items:center;justify-content:center;min-width:148px;min-height:48px;padding:10px 28px;border-radius:var(--radius);font-size:var(--body-size);font-weight:var(--weight-medium);letter-spacing:.01em;color:var(--white);flex-shrink:0;white-space:nowrap;transition:transform var(--motion-fast) ease,box-shadow var(--motion-fast) ease,background var(--motion-fast) ease}
.btn-primary{background:linear-gradient(180deg,var(--accent),var(--accent-press));box-shadow:var(--shadow-btn),inset 0 1px 0 var(--btn-hl)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--accent-dark);transform:translateY(-1px)}
.btn-ink,.btn-secondary{background:var(--ink);box-shadow:var(--shadow-btn-ink),inset 0 1px 0 var(--btn-hl)}
.btn-ink:hover,.btn-secondary:hover{background:var(--ink-dark);transform:translateY(-1px)}
.btn:active,.btn.is-pressed{transform:translateY(1px);box-shadow:var(--hl-inset)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);color:var(--text-muted);box-shadow:none;cursor:not-allowed;transform:none}
.btn-text{background:var(--panel);color:var(--accent-dark);border:1px solid var(--accent-line);box-shadow:var(--hl-inset)}
.btn-small{min-width:0;min-height:40px;padding:8px 16px;font-size:var(--small-size)}
.text-link{display:inline-flex;align-items:center;min-height:24px;gap:var(--space-1);color:var(--accent-dark);text-decoration:underline;text-underline-offset:4px}
.topbar{position:relative;z-index:30;background:var(--paper-top);border-bottom:1px solid var(--line-soft)}
.topbar-in{position:relative;max-width:1320px;margin:auto;padding:0 40px;height:var(--header-height);display:flex;align-items:center;gap:32px}
.brand{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:var(--weight-bold);font-size:19px;letter-spacing:.03em;flex-shrink:0;min-height:32px}
.brand-mark{width:32px;height:32px;filter:drop-shadow(0 4px 8px var(--shadow-tint))}
.brand-zh{font-weight:var(--weight-normal);color:var(--text-muted)}
.tabs{display:flex;align-items:stretch;height:var(--header-height);flex:1;min-width:0}
.tabs ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px;height:100%}
.tabs li{height:100%;flex-shrink:0}
.tab{position:relative;display:flex;align-items:center;height:100%;padding:0 13px;font-size:15px;color:var(--text-muted);white-space:nowrap;transition:color var(--motion-fast) ease}
.tab::after{content:"";position:absolute;left:13px;right:13px;bottom:-1px;height:2px;border-radius:var(--radius);background:var(--accent);transform:scaleX(0);transition:transform .25s ease}
.tab:hover{color:var(--text)}
.tab:hover::after{transform:scaleX(.35)}
.tab[aria-current="page"]{color:var(--text)}
.tab[aria-current="page"]::after{transform:scaleX(1)}
.top-actions{display:flex;align-items:center;gap:16px;flex-shrink:0}
.login{display:inline-flex;align-items:center;justify-content:center;height:36px;padding:0 18px;border-radius:var(--radius);border:1px solid var(--accent-line);background:var(--accent-tint-soft);color:var(--accent);font-size:var(--small-size);font-weight:var(--weight-medium);white-space:nowrap;transition:background var(--motion-fast) ease,border-color var(--motion-fast) ease}
.login:hover{background:var(--accent-tint);border-color:var(--accent)}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;padding:0 0 0 16px;min-height:36px;width:auto;border-left:1px solid var(--line);font-size:var(--small-size);color:var(--text-muted);background:transparent;white-space:nowrap}
.language-control{position:relative}
.language-menu{position:absolute;right:0;top:calc(100% + 12px);min-width:176px;padding:8px;border:1px solid var(--line);border-radius:var(--radius);background:var(--panel);box-shadow:var(--shadow-card);z-index:35}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--radius)}
.language-menu a:hover,.language-menu a[aria-current]{background:var(--accent-tint);color:var(--accent-dark)}
.menu-toggle{display:none;min-width:44px;min-height:44px;align-items:center;justify-content:center;background:transparent;color:var(--ink);border-radius:var(--radius)}
.menu-toggle svg{width:24px;height:24px}
.mobile-drawer{display:none}
.nav-veil{position:fixed;inset:var(--header-height) 0 0;z-index:20;background:var(--veil)}
.site-footer{background:var(--panel-2);border-top:1px solid var(--line);padding-top:var(--space-6);padding-bottom:var(--space-4)}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:var(--space-6)}
.footer-grid>*{min-width:0}
.footer-brand p{margin-top:var(--space-2);color:var(--text-muted);max-width:40ch}
.footer-heading{font-size:var(--body-size);font-weight:var(--weight-bold);margin-bottom:var(--space-2)}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px 16px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:28px;font-size:var(--small-size)}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent-dark);text-decoration:underline}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;margin-top:var(--space-4)}
.footer-bottom{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:var(--space-2);border-top:1px solid var(--line);margin-top:var(--space-3);padding-top:var(--space-3);font-size:var(--small-size);color:var(--text-muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:var(--space-3)}
.reveal{transition:opacity var(--motion-normal) ease,transform var(--motion-normal) ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:80px;max-width:100%;overflow:hidden;margin-top:var(--space-3);margin-bottom:var(--space-4)}
#server-status>*{max-width:100%;min-width:0}
#server-status+*{margin-top:var(--space-4)}
@media(max-width:1180px){
  .topbar-in{gap:20px;padding:0 24px}
  .tab{padding:0 9px;font-size:var(--small-size)}
  .tab::after{left:9px;right:9px}
}
@media(max-width:980px){
  .tabs{overflow-x:auto;scrollbar-width:none}
  .tabs::-webkit-scrollbar{display:none}
  .footer-grid{gap:var(--space-3)}
  .top-actions{gap:8px}
}
@media(max-width:768px){
  :root{--gutter:20px;--section-space:40px;--heading-size:28px}
  h1{font-size:38px}
  .topbar-in{padding:0 20px;gap:12px}
  .topbar-in>.tabs{display:none}
  .top-actions{margin-left:auto;gap:8px}
  .lang{padding-left:8px}
  .menu-toggle{display:inline-flex}
  .mobile-drawer:not([hidden]){display:block;position:absolute;top:100%;left:0;right:0;background:var(--panel);border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:12px 20px;max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;box-shadow:var(--shadow-card);z-index:32}
  .mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:10px 12px;border-radius:var(--radius)}
  .mobile-drawer a[aria-current="page"]{background:var(--accent-tint);color:var(--accent-dark)}
  .drawer-languages{border-top:1px solid var(--line);margin-top:12px;padding-top:12px}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-brand{grid-column:1/-1}
  .grid-three{grid-template-columns:1fr}
  .grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,.decor-tilt{transform:none}
  .paper-region,.stripe-halo{max-width:100%;overflow-x:clip}
  .footer-grid{grid-template-columns:1fr}
  .brand{font-size:17px;gap:8px}
  .topbar-in{padding-inline:16px;gap:8px}
  .top-actions .lang-label{display:none}
  .login{padding-inline:12px}
}
@media(max-width:360px){
  :root{--gutter:16px}
  h1{font-size:34px}
  .top-actions{gap:4px}
  .brand-mark{width:28px;height:28px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending{opacity:1;transform:none;transition:none}
  .btn,.login,.tab,.tab::after{transition:none}
  .btn:hover,.btn:active{transform:none}
}