:root{
  color-scheme:light;
  --bg:#F9F9FC;
  --panel:#FFFFFF;
  --panel-2:#F1F3FA;
  --border:#E3E6F0;
  --accent:#2A63F2;
  --accent-dark:#1A47C2;
  --accent-2:#8A5CF6;
  --text:#12152A;
  --muted:#5B6078;
  --muted-2:#8B90A7;
  --success:#12A06B;
  --warn:#D98A0B;
  --error:#D9364A;
  --clear:transparent;
  --glow-a:rgba(42,99,242,.14);
  --glow-b:rgba(138,92,246,.12);
  --glow-fade:rgba(138,92,246,0);
  --tint-a:rgba(42,99,242,.07);
  --tint-b:rgba(138,92,246,.07);
  --tint-a-strong:rgba(42,99,242,.14);
  --shadow-a:rgba(42,99,242,.10);
  --shadow-a-strong:rgba(42,99,242,.12);
  --shadow-cta:rgba(42,99,242,.40);
  --shadow-ink:rgba(18,21,42,.06);
  --success-tint:rgba(18,160,107,.12);
  --warn-tint:rgba(217,138,11,.10);
  --error-tint:rgba(217,54,74,.08);
  --hi:rgba(255,255,255,.92);
  --hi-soft:rgba(255,255,255,.26);
  --glass:rgba(255,255,255,.74);
  --veil:rgba(18,21,42,.28);
  --bg-clear:rgba(249,249,252,0);
  --flag-red:var(--error);
  --flag-blue:var(--accent-dark);
  --flag-white:var(--panel);
  --grad:linear-gradient(100deg,var(--accent) 0%,var(--accent-2) 100%);
  --grad-cta:linear-gradient(135deg,var(--accent) 0%,var(--accent) 52%,var(--accent-2) 135%);
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Apple SD Gothic Neo","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Malgun Gothic","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --weight-normal:400;
  --weight-medium:500;
  --weight-semibold:600;
  --weight-bold:700;
  --weight-display:800;
  --fs-xs:12px;
  --fs-sm:14px;
  --fs-body:16px;
  --fs-lede:18px;
  --fs-h1:64px;
  --fs-h2:40px;
  --fs-h3:24px;
  --r-xs:6px;
  --r-sm:8px;
  --r-md:10px;
  --r-lg:12px;
  --r-xl:20px;
  --r-pill:999px;
  --r-round:50%;
  --r-flag:3px;
  --container:1280px;
  --reading:820px;
  --gutter:80px;
  --section-space:88px;
  --anchor-offset:96px;
  --toc-offset:12px;
  --toc-landing:92px;
  --ease:ease;
  --fast:.15s;
  --reveal-duration:.6s;
  --sh-card:0 1px 2px var(--shadow-ink),0 14px 32px -16px var(--shadow-a-strong);
  --sh-float:0 0 0 1px var(--border),0 18px 36px -14px var(--shadow-a-strong),0 4px 10px -4px var(--shadow-ink);
  --sh-window:inset 0 0 0 1px var(--hi),0 2px 6px var(--shadow-ink),0 48px 96px -32px var(--shadow-a-strong),0 24px 48px -24px var(--shadow-a);
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
html.nav-open{overflow:hidden}
body{margin:0;background:var(--bg);color:var(--text);font:var(--weight-normal) var(--fs-body)/1.5 var(--font-body);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}
[hidden]{display:none!important}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
a{color:var(--accent-dark);text-underline-offset:3px}
a:hover{color:var(--accent)}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
:where(h1,h2,h3){font-family:var(--font-display);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,4.45vw,72px);line-height:1.12;font-weight:var(--weight-display);letter-spacing:-.02em}
h2{font-size:var(--fs-h2);line-height:1.25;letter-spacing:-.02em;font-weight:var(--weight-bold)}
h3{font-size:var(--fs-h3);line-height:1.35;font-weight:var(--weight-bold)}
p{margin:0 0 20px}
small{font-size:var(--fs-xs)}
code{font-family:var(--font-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--panel-2);font-family:var(--font-mono)}
pre code{overflow-wrap:normal;white-space:pre}
:where(.grid,.win-body,.feature-detail,.footer-grid)>*{min-width:0}
.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:var(--section-space);padding-bottom:var(--section-space)}
.grid{display:grid;gap:24px;grid-template-columns:repeat(3,minmax(0,1fr))}
.stack{display:grid;gap:24px}
.no-break{white-space:nowrap}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.kw{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:var(--clear);-webkit-text-fill-color:var(--clear)}
.panel,.card{padding:28px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--sh-card)}
.card h3{margin-top:0}
.prose{line-height:1.85;overflow-wrap:break-word;min-width:0}
.prose h2{margin-top:56px;font-size:32px}
.prose h3{margin-top:32px}
.prose li{margin-bottom:8px}
.prose img{border-radius:var(--r-md)}
.prose blockquote{margin-inline:0}
.ornament-zone{position:relative;overflow-x:clip}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.ico{width:18px;height:18px;flex:none;display:block}
.line-icon{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:48px;padding:0 24px;border:1px solid var(--clear);border-radius:var(--r-md);font:var(--weight-semibold) var(--fs-body)/1.2 var(--font-body);text-decoration:none;white-space:nowrap;flex-shrink:0;transition:background-color var(--fast) var(--ease),box-shadow var(--fast) var(--ease)}
.btn svg{width:18px;height:18px;flex:none;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round;stroke-linejoin:round}
.btn-primary{color:var(--panel);background:var(--grad-cta);box-shadow:inset 0 1px 0 var(--hi-soft),0 16px 30px -14px var(--shadow-cta)}
.btn-primary:hover,.btn-primary.is-hover{color:var(--panel);background:var(--accent-dark)}
.btn-ghost,.btn-secondary{color:var(--accent);background:var(--panel);border-color:var(--accent);box-shadow:0 10px 22px -16px var(--shadow-a-strong)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--tint-a)}
.btn:active{box-shadow:inset 0 2px 5px var(--shadow-ink)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);border-color:var(--border);color:var(--muted);box-shadow:none;cursor:not-allowed}
.btn.is-focus{outline:2px solid var(--accent);outline-offset:3px}
.cta-row{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin-bottom:24px}
.site-top{position:relative;z-index:30;padding-top:12px}
.topbar{position:relative;z-index:26;display:flex;align-items:center;gap:24px;height:56px;padding:0 10px 0 16px;background:var(--glass);border:1px solid var(--border);border-radius:var(--r-lg);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);box-shadow:0 10px 28px -20px var(--shadow-a-strong)}
.brand{display:inline-flex;align-items:center;gap:10px;flex:none;text-decoration:none;color:var(--text)}
.brand-mark{width:30px;height:30px;flex:none;display:block}
.brand-word{font-family:var(--font-display);font-weight:var(--weight-display);font-size:19px;letter-spacing:-.01em}
.brand-zh{color:var(--muted);font-weight:var(--weight-medium)}
.desktop-nav{min-width:0;margin-inline:auto;overflow-x:auto}
.menu{display:flex;align-items:center;gap:2px;list-style:none;margin:0;padding:0}
.menu a{display:inline-flex;align-items:center;gap:6px;height:36px;padding:0 10px;border-radius:var(--r-sm);color:var(--muted);font-size:var(--fs-sm);font-weight:var(--weight-medium);text-decoration:none;white-space:nowrap;transition:color var(--fast) var(--ease),background-color var(--fast) var(--ease)}
.menu a svg,.lang svg{width:16px;height:16px;flex:none;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.menu a:hover{color:var(--text);background:var(--panel-2)}
.menu a[aria-current="page"]{color:var(--accent);background:var(--tint-a)}
.top-actions{display:flex;align-items:center;gap:8px;flex:none}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;min-width:44px;width:auto;padding:0 12px;border:1px solid var(--border);border-radius:var(--r-sm);background:var(--panel);color:var(--muted);font:var(--weight-medium) 13px/1 var(--font-body);cursor:pointer;white-space:nowrap}
.lang span{white-space:nowrap}
.lang-caret{font-size:11px;color:var(--muted-2)}
.language-box{position:relative}
.language-box>summary{list-style:none}
.language-box>summary::-webkit-details-marker{display:none}
.language-menu{position:absolute;right:0;top:calc(100% + 10px);z-index:4;min-width:180px;padding:8px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--panel);box-shadow:var(--sh-float)}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;color:var(--muted);text-decoration:none;border-radius:var(--r-xs)}
.language-menu a:hover,.language-menu a[aria-current="true"]{background:var(--tint-a);color:var(--accent)}
.login{display:inline-flex;align-items:center;justify-content:center;height:36px;padding:0 18px;border-radius:var(--r-sm);background:var(--accent);color:var(--panel);font-size:var(--fs-sm);font-weight:var(--weight-semibold);text-decoration:none;white-space:nowrap;box-shadow:inset 0 1px 0 var(--hi-soft),0 8px 18px -10px var(--shadow-cta)}
.login:hover{background:var(--accent-dark);color:var(--panel)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:8px;border:1px solid var(--border);border-radius:var(--r-sm);background:var(--panel)}
.menu-toggle svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round}
.mobile-drawer{position:absolute;top:calc(100% + 10px);left:0;right:0;z-index:3;padding:12px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--sh-float);max-height:calc(100dvh - 90px);overflow-y:auto;overscroll-behavior:contain}
.mobile-drawer a{display:flex;align-items:center;gap:12px;width:100%;min-height:44px;padding:10px 12px;text-decoration:none;color:var(--muted);border-radius:var(--r-sm)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current]{color:var(--accent);background:var(--tint-a)}
.mobile-drawer svg{width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.drawer-languages{border-top:1px solid var(--border);margin-top:12px;padding-top:12px}
.nav-veil{position:fixed;inset:0;z-index:25;border:0;background:var(--veil);cursor:default}
.site-footer{margin-top:48px;padding-top:56px;padding-bottom:32px;border-top:1px solid var(--border);background:var(--panel)}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr 1fr;gap:40px}
.footer-grid h2{margin:0 0 16px;font-size:var(--fs-sm);letter-spacing:0}
.footer-brand p{max-width:300px;margin-top:18px;color:var(--muted);font-size:var(--fs-sm);line-height:1.8}
.footer-list{display:grid;gap:8px;list-style:none;padding:0;margin:0}
.footer-list a{display:inline-flex;align-items:center;min-height:28px;color:var(--muted);font-size:var(--fs-sm);text-decoration:none}
.footer-list a:hover{color:var(--accent)}
.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(--border);font-size:var(--fs-xs);color:var(--muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:20px}
.footer-legal a{display:inline-flex;align-items:center;min-height:28px;color:var(--muted)}
.reveal{transition:opacity var(--reveal-duration) var(--ease),transform var(--reveal-duration) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:160px;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status+*{margin-top:32px}
#server-status :where(.grid,[class*="grid"]){min-width:0;max-width:100%}
@media(min-width:1181px){.mobile-drawer,.nav-veil{display:none!important}}
@media(max-width:1280px){:root{--gutter:40px}.topbar{gap:16px}.menu a{padding-inline:7px}}
@media(max-width:1180px){
  .desktop-nav{display:none}
  .top-actions{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media(max-width:768px){
  :root{--gutter:24px;--section-space:56px;--fs-h2:30px;--fs-h3:22px}
  h1{font-size:clamp(28px,6vw,40px)}
  .grid{grid-template-columns:minmax(0,1fr)}
  .topbar{gap:12px;padding-left:12px}
  .panel,.card{padding:24px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none}
  .ornament-zone{max-width:100%;overflow-x:clip}
  .topbar{gap:8px;padding-right:5px}
  .brand{gap:7px}
  .brand-word{font-size:17px}
  .top-actions{gap:5px;margin-left:auto}
  .top-actions>.language-box{display:none}
  .login{height:40px;padding-inline:14px}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:28px}
  .prose h2{font-size:28px}
  .btn{padding-inline:18px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
  *,*::before,*::after{transition-duration:0s!important;animation-duration:0s!important;animation-iteration-count:1!important}
}