:root{
  --bg:#E7EDF7;--bg-top:#F1F5FB;--bg-bottom:#E2E9F5;--panel:#F8FAFE;--panel-2:#DAE3F1;--panel-hi:#FFFFFF;--panel-tint:#EEF3FA;
  --border:#C6D2E5;--border-soft:#D9E1EE;--accent:#C8234F;--accent-dark:#8F1736;--coral:#F0703F;--text:#141A2B;--muted:#4D5972;--faint:#76829B;
  --success:#1F9466;--success-light:#3DB386;--warn:#D98A12;--warn-light:#EDAA45;--warn-dark:#8E5608;--error:#B3261E;
  --graphite:#1B2233;--graphite-2:#262F43;--graphite-ink:#8E9AB3;--hex-gray:#C5CFDF;--hex-gray-2:#AEBACD;--ice:#4F86E6;--white:#FFFFFF;--flag-red:#D52B3E;--flag-blue:#26407F;
  --accent-a06:rgba(200,35,79,.06);--accent-a10:rgba(200,35,79,.10);--accent-a14:rgba(200,35,79,.14);--accent-a18:rgba(200,35,79,.18);--accent-a28:rgba(200,35,79,.28);
  --coral-a07:rgba(240,112,63,.07);--coral-a12:rgba(240,112,63,.12);--coral-a30:rgba(240,112,63,.30);--ice-a09:rgba(79,134,230,.09);
  --ink-a08:rgba(27,34,51,.08);--ink-a14:rgba(27,34,51,.14);--ink-a22:rgba(27,34,51,.22);
  --white-a10:rgba(255,255,255,.10);--white-a20:rgba(255,255,255,.20);--white-a35:rgba(255,255,255,.35);--white-a45:rgba(255,255,255,.45);--white-a60:rgba(255,255,255,.60);--white-a85:rgba(255,255,255,.85);
  --success-a12:rgba(31,148,102,.12);--warn-a14:rgba(217,138,18,.14);--warn-a24:rgba(217,138,18,.24);
  --font-display:"Inter","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",Menlo,Consolas,"Liberation Mono",monospace;
  --r-xs:4px;--r-sm:6px;--r-md:8px;--r-pill:999px;--r-round:50%;
  --gutter:32px;--content-width:1240px;--reading-width:840px;--notice-height:36px;--nav-height:62px;--header-height:98px;--anchor-gap:84px;--toc-offset:12px;--toc-landing:92px;
  --shadow-panel:0 20px 50px -24px var(--accent-a10),inset 0 1px 0 var(--white);
  --ease: cubic-bezier(.2,.7,.2,1);--fast:.2s;--reveal-time:.35s;
  --size-body:16px;--size-small:13px;--size-h1:clamp(52px,5vw,66px);--size-h2:38px;--weight-heavy:900;
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:var(--anchor-gap)}
html,body{margin:0;padding:0}
body{font-family:var(--font-body);font-size:var(--size-body);line-height:1.65;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a{color:inherit;text-decoration:none}
p,h1,h2,h3,h4,ul,ol{margin:0}
ul,ol{padding:0}
img,svg{vertical-align:middle}
img{max-width:100%;height:auto}
svg{flex-shrink:0}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button,a,summary{-webkit-tap-highlight-color:var(--accent-a10)}
button{border:0}
button:disabled{cursor:not-allowed}
[hidden]{display:none!important}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
h1,h2,h3{font-family:var(--font-display);text-wrap:balance}
h1{font-size:var(--size-h1);line-height:1.12;font-weight:var(--weight-heavy);letter-spacing:-.02em}
h2{font-size:var(--size-h2);line-height:1.2;font-weight:var(--weight-heavy);letter-spacing:-.02em}
h3{font-size:22px;line-height:1.35;font-weight:800}
code{font-family:var(--font-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;border-radius:var(--r-sm);background:var(--graphite);color:var(--panel);font-family:var(--font-mono)}
pre code{overflow-wrap:normal}
.wrap{max-width:var(--content-width);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.reading-wrap{max-width:var(--reading-width);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.sec{padding-top:72px;padding-bottom:72px}
.grid{display:grid;gap:20px}
.grid>*{min-width:0}
.grid-three{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-five{grid-template-columns:repeat(5,minmax(0,1fr))}
.no-break{white-space:nowrap}
.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.svg-defs{position:absolute;width:0;height:0;overflow:hidden}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.kw{color:var(--accent)}
.kicker{font-family:var(--font-mono);font-size:12px;font-weight:700;letter-spacing:.1em;color:var(--accent)}
.section-head{margin-bottom:28px}
.section-head h2{margin-top:8px}
.section-head p{margin-top:12px;color:var(--muted)}
.panel,.card{min-width:0;padding:24px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:var(--shadow-panel)}
.card h3+p{margin-top:12px;color:var(--muted)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:46px;padding:0 28px;border-radius:var(--r-sm);font-size:15px;font-weight:700;letter-spacing:.01em;flex-shrink:0;white-space:nowrap;transition:transform var(--fast) var(--ease),box-shadow var(--fast),background-color var(--fast)}
.btn-primary{min-width:168px;background:var(--accent);color:var(--white);box-shadow:inset 0 1px 0 var(--white-a35),0 0 0 1px var(--accent-dark),0 14px 30px -12px var(--accent-a28)}
.btn-primary:hover,.btn-primary.is-hover{transform:translateY(-1px);background:var(--accent-dark)}
.btn-ghost,.btn-secondary{min-width:148px;background:var(--white-a60);color:var(--text);box-shadow:inset 0 0 0 1px var(--text)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--panel-hi)}
.btn-small{min-width:0;min-height:36px;padding-inline:16px;font-size:13px}
.btn:active,.btn.is-active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);color:var(--muted);box-shadow:inset 0 0 0 1px var(--border);transform:none}
.btn.is-focus{outline:2px solid var(--accent);outline-offset:3px}
.cta{margin-top:18px;display:flex;justify-content:center;gap:12px;flex-wrap:wrap}
.notice{display:flex;align-items:center;justify-content:center;gap:10px;min-height:var(--notice-height);background:linear-gradient(90deg,var(--accent) 0%,var(--accent) 22%,var(--coral) 100%);color:var(--white);font-size:13.5px;font-weight:600;letter-spacing:.02em;padding-inline:16px}
.notice-sep{opacity:.7}
.notice-go{display:inline-flex;align-items:center;justify-content:center;gap:4px;min-height:24px;margin-left:6px;padding:2px 9px;border-radius:var(--r-pill);background:var(--white-a20);font-size:12px;font-weight:600}
.notice-go:hover{background:var(--white-a35)}
#site-header{position:relative;z-index:100}
.topbar{position:relative;z-index:104;background:var(--white-a60);backdrop-filter:blur(14px) saturate(1.3);-webkit-backdrop-filter:blur(14px) saturate(1.3);border-bottom:1px solid var(--border-soft)}
.topbar-in{max-width:var(--content-width);margin:0 auto;padding-inline:var(--gutter);height:var(--nav-height);display:flex;align-items:center;gap:40px;flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;flex:none}
.brand img{width:30px;height:30px;flex-shrink:0}
.brand-word{font-family:var(--font-display);font-size:19px;font-weight:900;letter-spacing:-.02em;color:var(--text)}
.brand-zh{font-weight:500;color:var(--muted)}
.desktop-nav{flex:1;min-width:0}
.nav-links{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:30px}
.nav-links a{display:inline-flex;align-items:center;min-height:24px;font-size:14.5px;font-weight:500;color:var(--muted);white-space:nowrap;transition:color var(--fast)}
.nav-links a:hover{color:var(--text)}
.nav-links a[aria-current="page"]{color:var(--text);font-weight:700}
.nav-end{display:flex;align-items:center;gap:20px;flex-shrink:0;margin-left:auto}
.lang{position:relative;font-size:13.5px;font-weight:500;color:var(--muted)}
.lang-button{display:inline-flex;align-items:center;justify-content:center;gap:5px;min-height:36px;min-width:44px;width:auto;padding:4px 0;background:transparent;white-space:nowrap}
.lang-button span{white-space:nowrap}
.lang-panel{position:absolute;z-index:110;right:0;top:calc(100% + 8px);width:180px;padding:8px;background:var(--panel-hi);border:1px solid var(--border);border-radius:var(--r-sm);box-shadow:0 16px 40px var(--ink-a14)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-xs)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--panel-tint);color:var(--accent-dark)}
.btn-login{display:inline-flex;align-items:center;justify-content:center;height:36px;padding:0 18px;border-radius:var(--r-sm);background:var(--graphite);color:var(--white);font-size:13.5px;font-weight:700;white-space:nowrap;box-shadow:inset 0 1px 0 var(--white-a20),0 6px 16px -8px var(--ink-a22)}
.btn-login:hover{background:var(--graphite-2)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:4px;min-width:44px;min-height:44px;padding:10px;background:transparent;color:var(--text)}
.menu-line{display:block;width:20px;height:2px;background:currentColor;border-radius:var(--r-xs)}
.mobile-drawer{position:fixed;z-index:102;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}
.mobile-drawer ul{list-style:none;margin:0;padding:0}
.mobile-drawer a{display:flex;width:100%;align-items:center;min-height:44px;padding:12px 16px;border-bottom:1px solid var(--border-soft)}
.mobile-drawer a[aria-current]{color:var(--accent-dark);font-weight:700}
.drawer-languages{margin-top:16px;border-top:1px solid var(--border)}
.menu-veil{position:fixed;z-index:101;inset:var(--header-height) 0 0;background:var(--ink-a22);border:0}
html.nav-open{overflow:hidden}
.site-footer{background:var(--panel-2);border-top:1px solid var(--border);padding-top:48px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:40px}
.footer-brand p{margin-top:16px;max-width:340px;color:var(--muted);font-size:14px}
.footer-title{font-size:14px;font-weight:800;margin-bottom:12px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px 16px;list-style:none}
.footer-links a,.footer-languages a,.legal-links a{display:inline-flex;align-items:center;min-height:28px;font-size:13px}
.footer-links a:hover,.footer-languages a:hover,.legal-links 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;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-top:20px;font-size:12px;color:var(--muted)}
.legal-links{display:flex;flex-wrap:wrap;gap:16px}
.reveal{transition:opacity var(--reveal-time) var(--ease),transform var(--reveal-time) 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-top:24px;margin-bottom:32px}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:24px}
.prose{overflow-wrap:break-word}
.prose p,.prose ul,.prose ol{margin-block:16px;line-height:1.85}
.prose ul,.prose ol{padding-left:24px}
.prose h2{margin-top:48px;margin-bottom:20px;font-size:30px}
.prose h3{margin-top:28px;margin-bottom:12px}
.prose a{color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
.prose :is(section,h2,h3)[id]{scroll-margin-top:var(--anchor-gap)}
body:has(.toc-tabs) section[id]{scroll-margin-top:var(--toc-landing)}
@media(min-width:1101px) and (max-width:1279px){
  .topbar-in{gap:24px}.nav-links{gap:20px}.nav-end{gap:16px}
}
@media(max-width:1100px){
  .desktop-nav{display:none}.menu-toggle{display:inline-flex}.topbar-in{gap:16px}.nav-end{margin-left:auto;gap:12px}
  .footer-grid{grid-template-columns:1.2fr 1fr;gap:28px}.footer-brand{grid-column:1/-1}
}
@media(min-width:1101px){.mobile-drawer,.menu-veil{display:none!important}}
@media(max-width:768px){
  :root{--gutter:24px;--size-h1:clamp(28px,6vw,40px);--size-h2:30px}
  .grid-three{grid-template-columns:1fr}.grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}
  .sec{padding-top:48px;padding-bottom:48px}.footer-grid{grid-template-columns:1fr 1fr}
}
@media(max-width:640px){
  :root{--gutter:16px}.no-break{white-space:normal}
  .topbar-in{gap:8px}.brand{gap:6px}.brand-word{font-size:17px}.brand img{width:26px;height:26px}
  .nav-end{gap:6px;margin-left:auto}.lang-button{font-size:12px}.btn-login{padding-inline:12px;font-size:12px}
  .notice{gap:6px;font-size:12px}.notice-go{display:none}
  .footer-grid{grid-template-columns:1fr}.footer-brand{grid-column:auto}
  .panel,.card{padding:20px}.tilt,.tilt-card,[data-tilt]{transform:none;max-width:100%}
  .hero,.feat,.decorated-section{overflow-x:clip;max-width:100%}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none}
}