:root{
  --bg:#E1EAF6;
  --bg-panel:#F5F8FD;
  --bg-panel2:#D4DFEF;
  --surface:#FFFFFF;
  --border:#C3D1E6;
  --border-soft:#D6E0EE;
  --accent:#E5243B;
  --accent-dark:#B3122A;
  --accent-tint:rgba(229,36,59,.06);
  --accent-line:rgba(229,36,59,.26);
  --accent-glow:rgba(229,36,59,.10);
  --text:#121A33;
  --text-muted:#4E5C78;
  --text-faint:#7A88A4;
  --success:#14A06B;
  --success-tint:rgba(20,160,107,.14);
  --success-on-ink:#4FD19C;
  --success-tint-ink:rgba(79,209,156,.14);
  --warn:#C98200;
  --error:#B42318;
  --hero-top:#EAF1FA;
  --hero-bottom:#DCE6F3;
  --chrome-hi:#E6EDF7;
  --ink:#121A33;
  --ink-2:#1B2548;
  --ink-well:rgba(255,255,255,.04);
  --ink-line:rgba(255,255,255,.08);
  --ink-hi:rgba(255,255,255,.14);
  --on-ink:#E9EEF8;
  --on-ink-muted:#909DBB;
  --hi-on-accent:rgba(255,255,255,.24);
  --dot-r:#E58A92;
  --dot-a:#E6BD69;
  --dot-g:#7BC8A5;
  --flag-red:#DA2B3C;
  --flag-white:#FFFFFF;
  --flag-navy:#2A3A6E;
  --flag-black:#1C1C21;
  --flag-gold:#F1C232;
  --clear:transparent;
  --shadow-panel:inset 0 1px 0 var(--surface),0 40px 64px -22px var(--accent-glow),0 22px 44px -26px rgba(18,26,51,.20),0 1px 2px rgba(18,26,51,.06);
  --shadow-ink:0 28px 56px -18px rgba(18,26,51,.55),0 6px 14px rgba(18,26,51,.22);
  --shadow-row:0 1px 2px rgba(18,26,51,.05);
  --shadow-pop:0 18px 40px -16px rgba(18,26,51,.28),0 2px 6px rgba(18,26,51,.08);
  --shadow-btn:0 16px 30px -14px rgba(229,36,59,.60);
  --shadow-sticker:0 10px 22px -8px rgba(179,18,42,.45),0 2px 4px rgba(18,26,51,.18);
  --inset-groove:inset 0 1px 2px rgba(18,26,51,.09);
  --radius-sm:4px;
  --radius:6px;
  --radius-pill:999px;
  --radius-round:50%;
  --font-display:Georgia,"Times New Roman","Songti SC","STSong","Noto Serif CJK SC","Source Han Serif SC","Hiragino Mincho ProN","Yu Mincho","Nanum Myeongjo",serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei","Apple SD Gothic Neo","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --size-body:16px;
  --size-display:68px;
  --size-section:44px;
  --size-subhead:28px;
  --wrap:1360px;
  --gutter:40px;
  --section-space:72px;
  --anchor-offset:84px;
  --toc-offset:88px;
  --toc-landing:156px;
  --ease:cubic-bezier(.2,.7,.2,1);
}
*,*::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(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--size-body);line-height:1.6;-webkit-font-smoothing:antialiased}
html.nav-open{overflow:hidden}
a{color:inherit;text-underline-offset:3px}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button,select,input,textarea{color:var(--text)}
button{border:0}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
ul,ol{margin:0;padding:0}
h1,h2,h3{font-family:var(--font-display);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,5vw,72px);font-weight:900;line-height:1.1;letter-spacing:-.02em}
h2{font-size:var(--size-section);font-weight:800;line-height:1.15;letter-spacing:-.02em}
h3{font-size:var(--size-subhead);line-height:1.25;font-weight:800}
p{margin-top:0}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
[hidden]{display:none!important}
.wrap{max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter);width:100%;min-width:0}
.section{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.section-title{margin:0 0 24px}
.section-intro{max-width:48em;color:var(--text-muted);margin-bottom:32px}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid>*{min-width:0}
.panel,.card{background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-row)}
.panel{padding:24px}
.card{padding:24px}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.hl{color:var(--accent)}
.no-break{white-space:nowrap}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.eyebrow{margin:0 0 20px;font-family:var(--font-mono);font-size:13px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--text)}
.slash{color:var(--accent);margin-right:.32em}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:52px;padding:12px 26px;border:0;border-radius:var(--radius);font-family:var(--font-body);font-size:16px;font-weight:700;line-height:1.5;text-decoration:none;transition:transform .2s ease;flex-shrink:0;white-space:nowrap}
.btn:hover{transform:translateY(-2px)}
.btn:active{transform:translateY(0)}
.btn svg{width:16px;height:16px}
.btn-primary{color:var(--surface);background:linear-gradient(165deg,var(--accent) 0%,var(--accent) 55%,var(--accent-dark) 100%);box-shadow:inset 0 1px 0 var(--hi-on-accent),var(--shadow-btn)}
.btn-primary:hover{background:var(--accent-dark)}
.btn-ghost,.btn-secondary{color:var(--text);background:var(--surface);border:1px solid var(--border);box-shadow:var(--shadow-row)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--bg-panel)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.55;cursor:not-allowed;transform:none}
.btn-small{min-height:40px;padding:8px 16px;font-size:14px}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin:0 0 32px}
.pill-btn{display:inline-flex;align-items:center;justify-content:center;min-height:26px;padding:3px 14px;border-radius:var(--radius-pill);background:var(--accent);color:var(--surface);font-size:12.5px;font-weight:700;text-decoration:none;transition:transform .2s ease;white-space:nowrap}
.pill-btn:hover{transform:translateY(-1px)}
.ann-toggle{position:absolute;opacity:0;pointer-events:none}
.ann-toggle:checked + .notice{display:none}
.notice{background:var(--ink);color:var(--on-ink);font-size:13.5px}
.notice-in{display:flex;align-items:center;gap:16px;min-height:40px}
.notice-text{margin:0;flex:1;min-width:0}
.notice-tag{font-family:var(--font-mono);font-size:11.5px;font-weight:700;letter-spacing:.08em;color:var(--on-ink-muted);margin-right:10px}
.notice-x{display:inline-flex;align-items:center;justify-content:center;width:28px;height:28px;padding:0;background:var(--clear);color:var(--on-ink-muted);cursor:pointer;border-radius:var(--radius-sm);flex-shrink:0}
.notice-x svg{width:12px;height:12px}
.site-head{position:relative;z-index:20;background:var(--hero-top);border-bottom:1px solid var(--border-soft)}
.head-in{display:flex;align-items:center;gap:40px;height:68px;position:relative}
.brand{display:inline-flex;align-items:center;gap:10px;text-decoration:none;flex-shrink:0}
.brand-mark{width:34px;height:34px;display:block}
.brand-name{font-family:var(--font-display);font-weight:700;font-size:22px;letter-spacing:.01em;color:var(--text)}
.brand-zh{font-weight:500;color:var(--text-muted)}
.nav-list{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px}
.nav-list>li{position:relative}
.nav-link,.more-btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;height:40px;padding:0 14px;font-family:inherit;font-size:15px;font-weight:500;color:var(--text);text-decoration:none;background:var(--clear);border:0;border-radius:var(--radius);cursor:pointer;position:relative;white-space:nowrap}
.nav-link:hover,.more-btn:hover{background:var(--bg-panel2)}
.nav-link[aria-current="page"]::after,.more-btn.is-current::after{content:"";position:absolute;left:14px;right:14px;bottom:4px;height:2px;border-radius:var(--radius-sm);background:var(--text)}
.more-btn svg{width:10px;height:10px;color:var(--text-muted)}
.more-panel{position:absolute;top:100%;left:0;min-width:208px;padding:8px;background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-pop)}
.more-label{margin:2px 10px 6px;font-family:var(--font-mono);font-size:11px;font-weight:700;letter-spacing:.08em;color:var(--text-muted)}
.more-panel a{display:flex;align-items:center;min-height:40px;padding:8px 10px;border-radius:var(--radius-sm);font-size:14.5px;text-decoration:none;color:var(--text)}
.more-panel a:hover,.more-panel a[aria-current="page"]{background:var(--bg-panel2)}
.head-tools{margin-left:auto;display:flex;align-items:center;gap:10px}
.language-box{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;height:40px;padding:0 10px;font-family:inherit;font-size:14px;color:var(--text-muted);background:var(--clear);border:0;border-radius:var(--radius);cursor:pointer}
.lang span{white-space:nowrap}
.lang:hover{background:var(--bg-panel2)}
.lang .globe{width:16px;height:16px}
.lang .chev{width:10px;height:10px}
.language-panel{position:absolute;right:0;top:calc(100% + 8px);min-width:170px;padding:8px;border:1px solid var(--border);border-radius:var(--radius);background:var(--surface);box-shadow:var(--shadow-pop)}
.language-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;text-decoration:none;border-radius:var(--radius-sm)}
.language-panel a:hover,.language-panel a[aria-current="true"]{background:var(--bg-panel2)}
.btn-login{display:inline-flex;align-items:center;justify-content:center;height:40px;padding:0 20px;border:1px solid var(--border);border-radius:var(--radius);background:var(--surface);color:var(--text);font-size:15px;font-weight:600;text-decoration:none;box-shadow:var(--shadow-row);transition:transform .2s ease;white-space:nowrap;flex-shrink:0}
.btn-login:hover{transform:translateY(-1px)}
.nav-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;background:var(--clear);color:var(--text);border-radius:var(--radius)}
.nav-toggle svg{width:22px;height:22px}
.mobile-nav{display:none}
.nav-veil{position:fixed;inset:0;z-index:19;background:var(--ink-line);border:0}
.site-footer{background:var(--bg-panel);border-top:1px solid var(--border);padding-top:48px;padding-bottom:32px}
.footer-grid{display:grid;grid-template-columns:minmax(0,1.5fr) repeat(3,minmax(0,1fr));gap:40px}
.footer-grid>*{min-width:0}
.footer-about{margin:20px 0 12px;max-width:28em;color:var(--text-muted)}
.footer-title{font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;margin:0 0 16px;font-weight:700}
.footer-links{list-style:none;display:grid;gap:4px}
.footer-links a{display:inline-flex;align-items:center;min-height:32px;text-decoration:none;color:var(--text-muted);font-size:14px}
.footer-links a:hover{color:var(--text);text-decoration:underline}
.footer-bottom{display:flex;flex-wrap:wrap;align-items:center;gap:16px 24px;border-top:1px solid var(--border);margin-top:32px;padding-top:20px;font-size:13px;color:var(--text-muted)}
.footer-bottom p{margin:0}
.footer-bottom a{display:inline-flex;align-items:center;min-height:28px}
.prose{max-width:76ch;min-width:0;line-height:1.85}
.prose h2{margin:48px 0 20px}
.prose h3{margin:32px 0 16px}
.prose p{margin-bottom:20px}
.prose ul,.prose ol{padding-left:1.5em;margin-bottom:24px}
.prose li{margin-bottom:8px}
code{font-family:var(--font-mono);font-size:.9em;overflow-wrap:anywhere;background:var(--bg-panel2);border-radius:var(--radius-sm);padding:2px 5px}
pre{max-width:100%;overflow-x:auto;background:var(--ink);color:var(--on-ink);border-radius:var(--radius);padding:20px;line-height:1.65}
pre code{background:var(--clear);color:inherit;padding:0;overflow-wrap:normal;white-space:pre}
.reveal{transition:opacity .6s ease,transform .6s var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{display:block;position:static;min-width:0;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status+*{margin-top:24px}
#server-status>*{min-width:0;max-width:100%}
.decorated{position:relative;overflow-x:clip}
.tilt{transform:rotate(-.45deg)}
@media(max-width:1180px){
  :root{--gutter:28px}
  .head-in{gap:24px}
  .nav-link,.more-btn{padding-inline:10px}
}
@media(max-width:900px){
  .main-nav{display:none}
  .lang-text{display:none}
  .head-tools{margin-left:auto}
  .nav-toggle{display:inline-flex}
  .mobile-nav:not([hidden]){display:block;position:absolute;top:100%;left:0;right:0;z-index:22;padding:16px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius);max-height:calc(100dvh - 108px);overflow-y:auto;overscroll-behavior:contain;box-shadow:var(--shadow-pop)}
  .mobile-nav a{display:flex;align-items:center;width:100%;min-height:44px;padding:10px 14px;text-decoration:none;border-radius:var(--radius)}
  .mobile-nav a:hover,.mobile-nav a[aria-current]{background:var(--bg-panel2)}
  .mobile-nav .footer-title{margin:20px 14px 8px}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px}
}
@media(max-width:768px){
  :root{--gutter:16px;--section-space:48px;--size-section:30px;--size-subhead:24px}
  h1{font-size:40px}
  .head-in{height:60px;gap:12px}
  .notice{font-size:12.5px}
  .notice-tag{display:none}
  .notice-in{gap:10px;padding-top:6px;padding-bottom:6px}
  .cta-row{margin-bottom:24px}
  .cta-row .btn{flex:1 1 140px}
  .grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt{transform:none}
  .decorated>*{max-width:100%}
  .head-tools{gap:4px;margin-left:auto}
  .btn-login{padding-inline:12px}
  .brand{gap:7px}
  .brand-name{font-size:20px}
  .brand-mark{width:30px;height:30px}
  .grid{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .footer-bottom{align-items:flex-start}
  .panel,.card{padding:20px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}