:root {
  --c-bg:#E7EAF3;
  --c-hero-top:#EEF0F7;
  --c-hero-bottom:#E2E6F0;
  --c-panel:#F7F8FC;
  --c-panel-2:#DCE0EC;
  --c-groove:#EEF1F8;
  --c-groove-deep:#E1E5F0;
  --c-surface:#FFFFFF;
  --c-chrome-top:#FCFDFF;
  --c-chrome-bottom:#EEF1F7;
  --c-border:#C9CFDE;
  --c-border-soft:#D8DDE9;
  --c-accent:#E5AC10;
  --c-accent-2:#F3CB55;
  --c-accent-dark:#7E5A00;
  --c-ink:#151829;
  --c-ink-2:#2E3450;
  --c-slate:#5B6178;
  --c-slate-2:#8C92A8;
  --c-success:#1F8A5B;
  --c-warn:#C26A00;
  --c-error:#C8323C;
  --c-success-soft:rgba(31,138,91,.12);
  --c-success-ring:rgba(31,138,91,.35);
  --c-white:#FFFFFF;
  --c-white-hi:rgba(255,255,255,.95);
  --c-white-70:rgba(255,255,255,.7);
  --c-white-14:rgba(255,255,255,.14);
  --c-ink-04:rgba(21,24,41,.04);
  --c-ink-06:rgba(21,24,41,.06);
  --c-ink-08:rgba(21,24,41,.08);
  --c-ink-10:rgba(21,24,41,.10);
  --c-ink-14:rgba(21,24,41,.14);
  --c-ink-22:rgba(21,24,41,.22);
  --c-mist-10:rgba(92,116,176,.10);
  --c-mist-18:rgba(92,116,176,.18);
  --c-steel-glow:rgba(118,138,188,.36);
  --c-arc:rgba(91,97,120,.46);
  --c-arc-bed:rgba(255,255,255,.75);
  --c-clear:transparent;
  --fl-white:#FFFFFF;
  --fl-red-jp:#BC002D;
  --fl-red-sg:#EF3340;
  --fl-red-hk:#DE2910;
  --fl-red-us:#B22234;
  --fl-blue-us:#3C3B6E;
  --fl-green-it:#009246;
  --fl-red-it:#CE2B37;
  --font-display:"Inter","Noto Sans SC","Noto Sans JP","Noto Sans KR","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","Noto Sans JP","Noto Sans KR","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-window:12px;
  --r-card:10px;
  --r-sm:8px;
  --r-xs:6px;
  --r-mini:4px;
  --r-line:2px;
  --r-circle:50%;
  --r-pill:999px;
  --shadow-soft:0 1px 2px var(--c-ink-06),0 6px 16px -6px var(--c-ink-10),0 12px 26px -12px var(--c-mist-18);
  --shadow-window:inset 0 1px 0 var(--c-white-hi),0 1px 2px var(--c-ink-06),0 34px 72px -26px var(--c-ink-10),0 60px 120px -40px var(--c-mist-10),0 24px 60px -30px var(--c-mist-18);
  --shadow-float:0 1px 2px var(--c-ink-08),0 18px 44px -14px var(--c-ink-14),0 30px 70px -26px var(--c-mist-18);
  --shadow-button:inset 0 1px 0 var(--c-white-14),0 10px 24px -10px var(--c-ink-22),0 18px 36px -18px var(--c-mist-18);
  --gutter:40px;
  --content-width:1280px;
  --reading-width:800px;
  --header-height:64px;
  --anchor-offset:80px;
  --toc-offset:132px;
  --text-xs:12px;
  --text-sm:14px;
  --text-base:16px;
  --text-lede:19px;
  --text-h3:24px;
  --text-h2:36px;
  --text-display:clamp(52px,4.6vw,64px);
  --weight-normal:400;
  --weight-medium:500;
  --weight-semibold:600;
  --weight-ui:650;
  --weight-bold:700;
  --ease-out:cubic-bezier(.2,.65,.3,1);
  --time-ui:.2s;
  --time-reveal:.6s;
  --grid-size:48px;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
body{margin:0;background:var(--c-bg);color:var(--c-ink);font-family:var(--font-body);font-size:var(--text-base);line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
html.nav-open{overflow:hidden}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
a{color:inherit;text-underline-offset:.2em}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--c-ink);outline-offset:3px;border-radius:var(--r-xs)}
[hidden]{display:none!important}
h1,h2,h3{font-family:var(--font-display);color:var(--c-ink);text-wrap:balance;font-weight:var(--weight-bold)}
h1{font-size:var(--text-display);line-height:1.1;letter-spacing:-.02em;margin:0 0 24px}
h2{font-size:var(--text-h2);line-height:1.25;letter-spacing:-.02em;margin:0 0 24px}
h3{font-size:var(--text-h3);line-height:1.35;margin:0 0 16px}
p{margin:0 0 20px}
strong{font-weight:var(--weight-semibold)}
code{font-family:var(--font-mono);overflow-wrap:anywhere;background:var(--c-groove);border-radius:var(--r-mini);padding:.12em .3em}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--c-groove);border:1px solid var(--c-border);border-radius:var(--r-sm)}
pre code{padding:0;background:var(--c-clear);overflow-wrap:normal;white-space:pre}
hr{border:0;border-top:1px solid var(--c-border);margin:32px 0}
.wrap{width:100%;max-width:var(--content-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:80px;padding-bottom:80px}
.reading-wrap{max-width:var(--reading-width);margin-inline:auto;min-width:0}
.prose{min-width:0;overflow-wrap:break-word}
.prose h2{margin-top:48px}
.prose h3{margin-top:32px}
.prose p,.prose li{color:var(--c-slate);line-height:1.85}
.prose strong{color:var(--c-ink)}
.prose li+li{margin-top:8px}
.prose img{border-radius:var(--r-sm)}
.no-break{white-space:nowrap}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;margin:-1px;padding:0;border:0}
.muted{color:var(--c-slate)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.lede{margin:0;font-size:var(--text-lede);line-height:28px;color:var(--c-slate)}
.lede strong{color:var(--c-ink);font-weight:var(--weight-semibold)}
.duotone{font-size:clamp(24px,3vw,40px);line-height:1.5;color:var(--c-slate);max-width:1000px}
.duotone strong{color:var(--c-ink)}
.kicker{font-family:var(--font-mono);font-size:var(--text-xs);letter-spacing:.08em;color:var(--c-slate);margin-bottom:16px}
.icon{display:block;width:24px;height:24px;color:currentColor}
.icon-line{fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.flow-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.flow-grid>*{min-width:0}
.panel,.card{min-width:0;background:var(--c-panel);border:1px solid var(--c-border-soft);border-radius:var(--r-window);box-shadow:inset 0 1px 0 var(--c-white-hi),var(--shadow-soft);padding:24px}
.decor-section{position:relative;isolation:isolate;overflow-x:clip;max-width:100%}
.grid-decor{position:absolute;inset:0;z-index:-1;pointer-events:none;background-image:linear-gradient(var(--c-ink-04) 1px,var(--c-clear) 1px),linear-gradient(90deg,var(--c-ink-04) 1px,var(--c-clear) 1px);background-size:var(--grid-size) var(--grid-size)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;height:46px;padding:0 24px;border:1px solid var(--c-clear);border-radius:var(--r-pill);font-size:15px;font-weight:var(--weight-semibold);text-decoration:none;white-space:nowrap;flex-shrink:0;transition:transform var(--time-ui) var(--ease-out),box-shadow var(--time-ui) var(--ease-out)}
.btn svg{width:16px;height:16px}
.btn:hover{transform:translateY(-1px)}
.btn:active,.btn.is-pressed{transform:translateY(1px)}
.btn-primary{background:linear-gradient(180deg,var(--c-ink-2),var(--c-ink));color:var(--c-white);box-shadow:var(--shadow-button)}
.btn-ghost,.btn-secondary{background:var(--c-white-70);color:var(--c-ink);border-color:var(--c-border);box-shadow:inset 0 1px 0 var(--c-white-hi)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.5;pointer-events:none;transform:none}
.btn.is-hover{transform:translateY(-1px);box-shadow:var(--shadow-float)}
.btn.is-focus{outline:2px solid var(--c-ink);outline-offset:3px}
.cta-row{display:flex;justify-content:center;flex-wrap:wrap;gap:12px;margin-top:24px}
.topbar{background:var(--c-hero-top);border-bottom:1px solid var(--c-border-soft);position:relative;z-index:50}
.topbar-in{max-width:var(--content-width);margin:0 auto;padding:0 var(--gutter);height:var(--header-height);display:flex;align-items:center;gap:28px;position:relative}
.brand{display:inline-flex;align-items:center;gap:10px;text-decoration:none;color:var(--c-ink);font-family:var(--font-display);font-weight:var(--weight-bold);font-size:18px;letter-spacing:-.01em;flex:none;min-height:28px}
.brand-mark{display:block;width:28px;height:28px;flex:none}
.brand-zh{font-size:var(--text-sm);font-weight:var(--weight-medium);color:var(--c-slate)}
.tabs{margin-left:auto;height:100%}
.tabs ul{display:flex;align-items:center;height:100%;gap:2px;list-style:none;margin:0;padding:0}
.tabs li{height:100%}
.tab{position:relative;display:flex;align-items:center;height:100%;padding:0 12px;font-size:var(--text-sm);font-weight:var(--weight-medium);color:var(--c-slate);text-decoration:none;white-space:nowrap;transition:color var(--time-ui)}
.tab::after{content:"";position:absolute;left:12px;right:12px;bottom:-1px;height:2px;border-radius:var(--r-line);background:var(--c-ink);transform:scaleX(0);transform-origin:center;opacity:.35;transition:transform .25s ease,opacity .25s ease}
.tab:hover{color:var(--c-ink)}
.tab:hover::after{transform:scaleX(.45)}
.tab.is-active{color:var(--c-ink);font-weight:var(--weight-semibold)}
.tab.is-active::after{transform:scaleX(1);opacity:1}
.topbar-end{display:flex;align-items:center;gap:16px;padding-left:22px;border-left:1px solid var(--c-border-soft);height:24px;flex:none}
.language-control{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;background:var(--c-clear);border:0;padding:0;min-height:28px;width:auto;font:inherit;font-size:var(--text-sm);color:var(--c-slate);cursor:pointer;white-space:nowrap}
.lang svg{width:14px;height:14px}
.lang:hover{color:var(--c-ink)}
.language-menu{position:absolute;right:0;top:calc(100% + 14px);width:180px;padding:6px;background:var(--c-panel);border:1px solid var(--c-border);border-radius:var(--r-sm);box-shadow:var(--shadow-float)}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-xs);text-decoration:none;color:var(--c-slate)}
.language-menu a:hover,.language-menu a[aria-current]{background:var(--c-panel-2);color:var(--c-ink)}
.login-pill{display:inline-flex;align-items:center;justify-content:center;height:34px;padding:0 18px;border-radius:var(--r-pill);background:var(--c-ink);color:var(--c-white);font-size:var(--text-sm);font-weight:var(--weight-semibold);text-decoration:none;box-shadow:inset 0 1px 0 var(--c-white-14),0 6px 14px -8px var(--c-ink-22);white-space:nowrap;transition:transform var(--time-ui)}
.login-pill:hover{transform:translateY(-1px)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;border:0;border-radius:var(--r-xs);background:var(--c-clear);color:var(--c-ink)}
.menu-toggle svg{width:22px;height:22px}
.mobile-drawer{display:none}
.site-footer{padding-top:56px;padding-bottom:32px;background:var(--c-panel-2);border-top:1px solid var(--c-border);box-shadow:inset 0 1px 0 var(--c-white-70)}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1.2fr;gap:48px}
.footer-grid>*{min-width:0}
.footer-brand p{color:var(--c-slate);font-size:var(--text-sm);max-width:340px;margin-top:16px}
.footer-heading{font-size:var(--text-sm);font-weight:var(--weight-semibold);margin:0 0 16px}
.footer-links{display:flex;flex-wrap:wrap;gap:8px 20px;list-style:none;margin:0;padding:0}
.footer-links a{display:inline-flex;align-items:center;min-height:28px;text-decoration:none;font-size:var(--text-sm);color:var(--c-slate)}
.footer-links a:hover{color:var(--c-ink);text-decoration:underline}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:16px;margin-top:40px;padding-top:24px;border-top:1px solid var(--c-border);font-size:var(--text-xs);color:var(--c-slate)}
.footer-bottom p{margin:0}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 16px}
.footer-languages a{display:inline-flex;align-items:center;min-height:28px;text-decoration:none}
.footer-languages a[aria-current]{color:var(--c-ink);font-weight:var(--weight-semibold)}
.reveal{transition:opacity var(--time-reveal) ease,transform var(--time-reveal) var(--ease-out)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-width:0;min-height:96px;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}
@media(max-width:1180px){
  .topbar-in{gap:16px}
  .tab{padding-inline:8px}
  .tab::after{left:8px;right:8px}
  .topbar-end{gap:12px;padding-left:16px}
}
@media(max-width:1050px){
  .tabs{display:none}
  .topbar-end{margin-left:auto;border-left:0;padding-left:0}
  .menu-toggle{display:inline-flex}
  .mobile-drawer:not([hidden]){display:block;position:absolute;top:var(--header-height);left:0;right:0;z-index:51;background:var(--c-panel);border-bottom:1px solid var(--c-border);padding:12px var(--gutter) 20px;max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;box-shadow:var(--shadow-float)}
  .mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px;text-decoration:none;border-radius:var(--r-xs);color:var(--c-slate)}
  .mobile-drawer a[aria-current],.mobile-drawer a:hover{color:var(--c-ink);background:var(--c-panel-2)}
  .drawer-languages{margin-top:12px;padding-top:12px;border-top:1px solid var(--c-border)}
}
@media(max-width:768px){
  :root{--gutter:24px;--text-display:clamp(28px,6vw,40px);--text-h2:28px;--text-h3:21px}
  .flow-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
  .footer-brand{grid-column:1/-1}
  .section{padding-top:48px;padding-bottom:48px}
  .decor-section{max-width:100%}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .topbar-in{gap:8px}
  .brand{gap:7px;font-size:16px}
  .brand-mark{width:24px;height:24px}
  .topbar-end{gap:8px;margin-left:auto}
  .lang{font-size:var(--text-xs)}
  .login-pill{padding-inline:12px}
  .flow-grid,.footer-grid{grid-template-columns:minmax(0,1fr)}
  .panel,.card{padding:20px}
  .tilt,.devcard{transform:none}
  .prose{width:100%}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
  *,*::before,*::after{animation-duration:0s!important;animation-iteration-count:1!important;transition-duration:0s!important}
}