:root{
  color-scheme:light;
  --bg:#FAFAFC;
  --bg-panel:#FFFFFF;
  --bg-panel-2:#F2F2F7;
  --bg-sunk:#F7F7FA;
  --border:#E4E4EC;
  --border-strong:#D5D5DF;
  --accent:#5E48E8;
  --accent-2:#8E7CFF;
  --accent-dark:#3B2BAE;
  --accent-6:rgb(94 72 232 / .06);
  --accent-10:rgb(94 72 232 / .10);
  --accent-14:rgb(94 72 232 / .14);
  --accent-28:rgb(94 72 232 / .28);
  --text:#14131C;
  --text-muted:#5E5D6E;
  --text-faint:#8D8C9C;
  --ink:#14131C;
  --ink-2:#24232F;
  --ink-4:rgb(20 19 28 / .04);
  --ink-8:rgb(20 19 28 / .08);
  --ink-12:rgb(20 19 28 / .12);
  --on-ink:#FFFFFF;
  --on-ink-muted:rgb(255 255 255 / .62);
  --on-ink-line:rgb(255 255 255 / .22);
  --on-ink-hl:rgb(255 255 255 / .16);
  --on-ink-trace:rgb(255 255 255 / .06);
  --success:#1F9D6A;
  --success-14:rgb(31 157 106 / .14);
  --warn:#C98A12;
  --error:#D2394B;
  --hl:rgb(255 255 255 / .92);
  --hl-soft:rgb(255 255 255 / .5);
  --panel-glass:rgb(255 255 255 / .86);
  --trace:#E2E2EA;
  --trace-strong:#D3D3DD;
  --trace-fill:#FFFFFF;
  --flag-red:#D22F3C;
  --flag-blue:#2B3F8C;
  --flag-white:#FFFFFF;
  --flag-edge:rgb(20 19 28 / .12);
  --mask-solid:#000000;
  --clear:transparent;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","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;
  --r-xs:4px;
  --r-sm:6px;
  --r-md:8px;
  --r-pill:999px;
  --r-circle:50%;
  --container:1240px;
  --reading:820px;
  --gutter:24px;
  --anchor-offset:96px;
  --toc-offset:20px;
  --toc-landing:100px;
  --shadow-panel:0 1px 2px var(--ink-4),0 4px 10px var(--ink-4),0 20px 40px var(--accent-10);
  --shadow-back:0 1px 2px var(--ink-4),0 14px 40px var(--accent-6);
  --main-w:720px;
  --float-w:296px;
  --ov:36px;
  --ease-ui:cubic-bezier(.2,.7,.2,1);
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:15px;line-height:1.6;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
html.nav-open{overflow:hidden}
a{color:inherit;text-underline-offset:4px}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled,[aria-disabled="true"]{cursor:not-allowed}
button,summary,a,input,select,textarea,[tabindex]{-webkit-tap-highlight-color:var(--accent-14)}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
button{border:0}
img,svg{vertical-align:middle;max-width:100%}
img{height:auto}
svg{flex-shrink:0}
p{margin:0}
ul,ol{padding-left:1.5em}
h1,h2,h3,h4{font-family:var(--font-display);margin:0 0 18px;line-height:1.25;text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,4.6vw,66px);font-weight:900;letter-spacing:-.02em;line-height:1.1}
h2{font-size:clamp(28px,3vw,40px);font-weight:800;letter-spacing:-.02em}
h3{font-size:22px;font-weight:750;letter-spacing:-.01em}
h4{font-size:17px;font-weight:700}
.no-break{white-space:nowrap}
code,kbd,pre{font-family:var(--font-mono)}
code{overflow-wrap:anywhere;font-size:.9em}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--bg-panel-2);border:1px solid var(--border);border-radius:var(--r-sm);line-height:1.8}
pre code{overflow-wrap:normal;white-space:pre}
[hidden]{display:none!important}
.wrap{width:100%;max-width:calc(var(--container) + var(--gutter)*2);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:calc(var(--reading) + var(--gutter)*2);margin-inline:auto;padding-inline:var(--gutter)}
.sec{padding-top:72px;padding-bottom:72px}
.section-head{max-width:820px;margin-bottom:32px}
.section-head p{font-size:18px;color:var(--text-muted)}
.grid{display:grid;gap:24px}
.grid>*{min-width:0}
.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-5{grid-template-columns:repeat(5,minmax(0,1fr))}
.stack{display:grid;gap:20px}
.stack>*{min-width:0}
.panel,.card{min-width:0;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:inset 0 1px 0 var(--hl),var(--shadow-back)}
.panel{padding:28px}
.card{padding:24px}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.muted{color:var(--text-muted)}
.kicker{font-family:var(--font-mono);font-size:12px;letter-spacing:.14em;color:var(--text-muted);margin-bottom:16px}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.ico{width:16px;height:16px;flex:none;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.btn{display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;gap:8px;min-height:48px;padding:10px 26px;border-radius:var(--r-sm);font-size:16px;font-weight:600;text-decoration:none;white-space:nowrap;transition:transform .15s ease,box-shadow .15s ease}
.btn:hover,.btn.is-hover{transform:translateY(-1px)}
.btn-primary{color:var(--on-ink);background:linear-gradient(180deg,var(--accent-2) -35%,var(--accent) 55%,var(--accent-dark) 150%);box-shadow:inset 0 1px 0 var(--on-ink-line),0 1px 2px var(--accent-28),0 10px 24px var(--accent-14)}
.btn-primary .ico{width:17px;height:17px;stroke-width:2}
.btn-secondary{color:var(--text);background:var(--bg-panel);border:1px solid var(--border);box-shadow:inset 0 1px 0 var(--hl),0 1px 2px var(--ink-4)}
.btn-secondary:hover{border-color:var(--border-strong)}
.btn:active,.btn.is-active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--bg-panel-2);color:var(--text-muted);box-shadow:none;transform:none;border:1px solid var(--border)}
.btn.is-focus{outline:2px solid var(--accent);outline-offset:3px}
.btn-small{min-height:40px;padding:8px 16px;font-size:14px}
.btn-ink{background:linear-gradient(180deg,var(--ink-2),var(--ink));color:var(--on-ink);box-shadow:inset 0 1px 0 var(--on-ink-hl)}
.link-row{display:flex;flex-wrap:wrap;align-items:center;gap:12px}
.link-row a{display:inline-flex;align-items:center;min-height:28px}
.announce{position:relative;background:var(--ink);color:var(--on-ink);overflow:hidden}
.announce::before{content:"";position:absolute;top:0;bottom:0;left:26%;right:26%;background:var(--ink-2);clip-path:polygon(0 0,100% 0,calc(100% - 22px) 100%,22px 100%)}
.announce-in{position:relative;display:flex;justify-content:center;align-items:center;gap:16px;min-height:40px;padding:6px 16px;font-size:14px;font-weight:500;letter-spacing:.01em}
.announce-sep{width:1px;height:16px;background:var(--on-ink-line);flex:none}
.announce a{display:inline-flex;align-items:center;gap:6px;min-height:24px;flex:none;text-decoration:none;color:var(--on-ink)}
.announce a:hover{color:var(--on-ink-muted)}
.announce-arrow{font-size:10px;color:var(--on-ink-muted)}
#site-header{position:relative;z-index:30}
.nav-wrap{position:relative;z-index:3;padding:12px 24px 0}
.nav{position:relative;max-width:var(--container);height:56px;margin:0 auto;display:flex;align-items:center;gap:4px;padding:0 10px 0 16px;background:var(--panel-glass);-webkit-backdrop-filter:blur(10px);backdrop-filter:blur(10px);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:inset 0 1px 0 var(--hl),0 1px 2px var(--ink-4),0 8px 24px var(--accent-6)}
.brand{display:inline-flex;align-items:center;gap:9px;text-decoration:none;padding-right:14px;flex:none;min-height:36px}
.brand-mark{width:28px;height:28px;display:block;flex:none}
.brand-word{font-family:var(--font-display);font-size:18px;font-weight:800;letter-spacing:-.02em;color:var(--text)}
.nav-divider{width:1px;height:24px;background:var(--border);margin-right:8px;flex:none}
.nav-list{display:flex;align-items:center;gap:2px;list-style:none;margin:0;padding:0}
.desktop-nav{min-width:0}
.nav-link{display:inline-flex;align-items:center;gap:7px;min-height:36px;padding:0 11px;border-radius:var(--r-sm);font-size:14px;font-weight:500;color:var(--text-muted);text-decoration:none;white-space:nowrap;transition:background-color .15s,color .15s}
.nav-link:hover{background:var(--bg-panel-2);color:var(--text)}
.nav-link[aria-current="page"]{background:var(--bg-panel-2);color:var(--text)}
.nav-link .ico{color:var(--text-faint)}
.nav-link:hover .ico,.nav-link[aria-current="page"] .ico{color:var(--text)}
.nav-end{margin-left:auto;display:flex;align-items:center;gap:6px;flex:none}
.lang-box{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;min-height:36px;padding:0 10px;border:0;background:var(--clear);border-radius:var(--r-sm);font-size:14px;font-weight:500;color:var(--text-muted);cursor:pointer;white-space:nowrap}
.lang span{white-space:nowrap}
.lang:hover{background:var(--bg-panel-2);color:var(--text)}
.lang-caret{font-size:11px;color:var(--text-faint)}
.lang-menu{position:absolute;right:0;top:calc(100% + 12px);width:190px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:var(--shadow-panel);z-index:40}
.lang-menu a{display:flex;align-items:center;min-height:40px;padding:8px 12px;text-decoration:none;border-radius:var(--r-sm)}
.lang-menu a:hover,.lang-menu a[aria-current="true"]{background:var(--bg-panel-2);color:var(--accent-dark)}
.login{display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:36px;padding:0 16px;border-radius:var(--r-sm);background:linear-gradient(180deg,var(--ink-2),var(--ink));color:var(--on-ink);font-size:14px;font-weight:600;text-decoration:none;white-space:nowrap;box-shadow:inset 0 1px 0 var(--on-ink-hl),0 1px 2px var(--ink-12)}
.login .ico{width:15px;height:15px}
.login:hover{background:var(--ink)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;background:var(--clear);border-radius:var(--r-sm)}
.mobile-drawer{display:none}
.mobile-drawer a{display:flex;align-items:center;gap:12px;width:100%;min-height:44px;padding:12px 16px;text-decoration:none;border-radius:var(--r-sm)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current="page"]{background:var(--bg-panel-2);color:var(--accent-dark)}
.drawer-label{padding:16px 16px 4px;font-size:12px;font-family:var(--font-mono);color:var(--text-muted)}
.drawer-languages{border-top:1px solid var(--border);margin-top:12px;padding-top:8px}
.site-footer{margin-top:48px;background:var(--bg-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 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-brand p{color:var(--text-muted);max-width:320px;margin-top:14px}
.footer-title{font-size:14px;font-weight:700;margin:0 0 12px}
.footer-list{list-style:none;margin:0;padding:0;display:grid;gap:6px}
.footer-list a{display:inline-flex;align-items:center;min-height:28px;text-decoration:none;color:var(--text-muted)}
.footer-list a:hover{color:var(--accent-dark);text-decoration:underline}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;border-top:1px solid var(--border);padding-top:20px;margin-top:36px;color:var(--text-muted);font-size:13px}
.footer-legal{display:flex;flex-wrap:wrap;gap:16px}
.footer-legal a{display:inline-flex;align-items:center;min-height:28px}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol{margin:0 0 22px}
.prose h2{margin-top:48px}
.prose h3{margin-top:30px}
.prose li+li{margin-top:8px}
.prose a{color:var(--accent-dark)}
.prose blockquote{margin-inline:0}
.prose img{max-width:100%;border-radius:var(--r-sm)}
.decorated{position:relative;overflow-x:clip;max-width:100%}
#server-status{position:relative;display:block;min-width:0;max-width:100%;min-height:180px;overflow:hidden;margin:24px 0}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:24px}
.reveal{transition:opacity .6s var(--ease-ui),transform .6s var(--ease-ui)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
@media(max-width:1279px){
  :root{--main-w:640px;--float-w:244px;--ov:40px}
}
@media(max-width:1100px){
  .nav-link{padding-inline:9px}
  .nav-text{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}
}
@media(max-width:900px){
  .grid-5{grid-template-columns:repeat(3,minmax(0,1fr))}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media(max-width:768px){
  :root{--gutter:16px}
  h1{font-size:clamp(28px,7vw,40px)}
  .announce::before{left:3%;right:3%}
  .announce-in{gap:10px;font-size:12px}
  .nav-wrap{padding:10px 12px 0}
  .nav{padding-left:12px}
  .desktop-nav,.nav-divider{display:none}
  .nav-end{margin-left:auto;gap:2px}
  .brand{padding-right:0;gap:7px}
  .lang-text{display:none}
  .lang{padding-inline:8px;min-height:44px}
  .login{min-height:40px;padding-inline:12px}
  .menu-toggle{display:inline-flex}
  .mobile-drawer:not([hidden]){display:block;position:absolute;top:calc(100% + 8px);left:0;right:0;padding:12px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);max-height:calc(100dvh - 124px);overflow-y:auto;overscroll-behavior:contain;box-shadow:var(--shadow-panel);z-index:35}
  .nav-text{position:static;width:auto;height:auto;clip-path:none;overflow:visible}
  .sec{padding-top:48px;padding-bottom:48px}
  .grid-3,.grid-2{grid-template-columns:minmax(0,1fr)}
  .panel{padding:22px}
  .grid-5{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-grid{gap:28px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none}
  .decorated,.stripe-halo{max-width:100%;overflow-x:clip}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .announce-in{gap:7px;font-size:11px}
  .announce-sep{height:12px}
  .card{padding:20px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
  .btn,.nav-link{transition:none}
  .btn:hover{transform:none}
}