:root{
  --bg:#F9F2E6;--bg-top:#FCF8F0;--bg-bottom:#F3EAD9;
  --panel:#FFFCF6;--panel-2:#EFE5D3;--panel-soft:#F8F1E4;
  --border:#E3D6C0;--border-soft:rgba(42,33,24,.08);
  --accent:#3346D3;--accent-2:#3D9BE6;--accent-dark:#2433A6;--accent-line:rgba(51,70,211,.14);
  --ink:#2A2118;--muted:#6E6152;--faint:#9A8B78;
  --success:#2F8A57;--success-soft:rgba(47,138,87,.14);--warn:#B8730F;--error:#C23B2E;
  --on-accent:#FFFCF6;--on-ink-muted:rgba(255,252,246,.66);
  --apricot:#F6DDBF;--butter:#F8EBC3;--dot:#CDBFA8;
  --grid-line:rgba(42,33,24,.03);--glow:rgba(246,221,191,.78);--mask:#000;
  --bar-bg:rgba(252,248,240,.86);--hi:rgba(255,255,255,.9);--hi-on-accent:rgba(255,255,255,.3);
  --frame-hi:rgba(255,248,236,.16);--groove-in:rgba(42,33,24,.09);
  --sh-tint:rgba(51,70,211,.10);--sh-tint-lg:rgba(51,70,211,.15);
  --sh-warm:rgba(42,33,24,.10);--sh-warm-sm:rgba(42,33,24,.06);
  --flag-red:#D7322B;--flag-blue:#25408F;--flag-white:#FFFFFF;
  --clear:transparent;--veil:rgba(42,33,24,.3);
  --grad:linear-gradient(100deg,var(--accent) 0%,var(--accent-2) 100%);
  --grad-mark:linear-gradient(140deg,var(--accent) 0%,var(--accent-dark) 100%);
  --font-display:"Inter","Noto Sans SC","Noto Sans JP","Noto Sans KR","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","Noto Sans JP","Noto Sans KR","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,"Liberation Mono",monospace;
  --r-xs:6px;--r-sm:10px;--r-md:14px;--r-lg:18px;--r-xl:26px;--r-pill:999px;--r-round:50%;
  --r-frame:16px;--r-tray:30px;--r-button:12px;--r-flag:4px;--r-flag-lg:7px;--r-segment:8px;
  --gutter:56px;--header-height:72px;--anchor-offset:88px;--toc-offset:156px;
  --text-xs:12px;--text-sm:14px;--text-base:16px;--text-lg:18px;
  --display-size:66px;--heading-size:36px;--subheading-size:24px;
  --weight-normal:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-heavy:800;--weight-display:900;
  --shadow-panel:inset 0 1px 0 var(--hi),0 24px 48px -24px var(--sh-tint),0 4px 12px -6px var(--sh-warm);
  --ease: cubic-bezier(.2,.6,.3,1);--quick:.2s;--reveal-time:.35s;
}
*,*::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(--ink);font-family:var(--font-body);font-size:var(--text-base);line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
main,section,article,aside,nav,div,li{min-width:0}
img,video{max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
ul{margin:0;padding:0;list-style:none}
p,h1,h2,h3,h4{margin:0}
h1,h2,h3{font-family:var(--font-display);text-wrap:balance}
h1{font-size:var(--display-size);font-weight:var(--weight-display);line-height:1.1;letter-spacing:-.02em}
h2{font-size:var(--heading-size);font-weight:var(--weight-heavy);line-height:1.2;letter-spacing:-.02em}
h3{font-size:var(--subheading-size);font-weight:var(--weight-bold);line-height:1.35}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;padding:0;cursor:pointer}
svg{flex-shrink:0;display:block}
button,a,summary{touch-action:manipulation}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:var(--r-xs)}
[hidden]{display:none!important}
.no-break{white-space:nowrap}
.wrap{width:100%;max-width:1400px;margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:72px;padding-bottom:72px}
.section-head{margin-bottom:32px}
.section-head p{margin-top:12px;max-width:720px;color:var(--muted)}
.reading-wrap{max-width:900px;margin-inline:auto;padding-inline:var(--gutter)}
.prose{overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote,.prose table{margin-block:20px}
.prose h2{margin-top:48px;margin-bottom:20px}
.prose h3{margin-top:32px;margin-bottom:12px}
.prose ul{padding-left:24px;list-style:disc}
.prose ol{padding-left:26px}
.prose li+li{margin-top:8px}
.prose a{text-decoration:underline;text-underline-offset:4px;color:var(--accent-dark)}
code{font-family:var(--font-mono);overflow-wrap:anywhere;background:var(--panel-2);border-radius:var(--r-xs);padding:2px 5px;font-size:.88em}
pre{max-width:100%;overflow-x:auto;background:var(--panel-2);border:1px solid var(--border);border-radius:var(--r-md);padding:20px}
pre code{padding:0;white-space:pre;overflow-wrap:normal;background:var(--clear)}
.skip{position:absolute;left:-9999px;top:12px;z-index:100;padding:8px 16px;background:var(--ink);color:var(--on-accent);border-radius:var(--r-sm)}
.skip:focus{left:16px}
.ic{fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;width:20px;height:20px}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.panel,.card{background:var(--panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--shadow-panel);padding:24px}
.grid-two{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px}
.grid-three{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.stack{display:grid;gap:20px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:54px;padding:12px 26px;border-radius:var(--r-md);font-size:16.5px;font-weight:var(--weight-bold);flex-shrink:0;white-space:nowrap;transition:transform var(--quick),box-shadow var(--quick)}
.btn-primary{background:var(--grad);color:var(--on-accent);box-shadow:inset 0 1px 0 var(--hi-on-accent),0 16px 30px -14px var(--sh-tint-lg),0 4px 10px -6px var(--sh-tint-lg)}
.btn-primary:hover{transform:translateY(-1px);box-shadow:inset 0 1px 0 var(--hi-on-accent),0 20px 34px -14px var(--sh-tint-lg)}
.btn-ghost,.btn-secondary{background:var(--panel);color:var(--ink);border:1px solid var(--border);box-shadow:inset 0 1px 0 var(--hi),0 2px 6px -2px var(--sh-warm-sm)}
.btn-ghost:hover,.btn-secondary:hover{transform:translateY(-1px);border-color:var(--dot)}
.btn:active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.5;cursor:not-allowed;transform:none}
.btn-small{min-height:44px;padding:8px 18px;font-size:var(--text-sm)}
.cta-row{margin-top:32px;display:flex;align-items:center;flex-wrap:wrap;gap:12px}
#site-header{position:sticky;top:0;z-index:80}
.topbar{position:relative;z-index:83;background:var(--bar-bg);-webkit-backdrop-filter:blur(14px);backdrop-filter:blur(14px);border-bottom:1px solid var(--border-soft)}
.topbar-in{height:var(--header-height);display:flex;align-items:center;gap:40px;flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0}
.brand-mark{display:block;width:34px;height:34px;border-radius:var(--r-sm)}
.brand-word{font-family:var(--font-display);font-weight:var(--weight-display);font-size:20px;letter-spacing:-.02em}
.brand-zh{font-size:var(--text-sm);font-weight:var(--weight-medium);color:var(--muted);padding-left:10px;border-left:1px solid var(--border)}
.mainnav{flex:1;min-width:0}
.mainnav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:4px}
.mainnav a,.more-btn{position:relative;display:inline-flex;align-items:center;gap:6px;min-height:40px;padding:8px 14px;border-radius:var(--r-pill);font-size:15px;font-weight:var(--weight-medium);color:var(--muted);white-space:nowrap}
.mainnav a:hover,.more-btn:hover{background:var(--panel);color:var(--ink)}
.mainnav a[aria-current="page"],.more-btn.is-current{color:var(--ink);font-weight:var(--weight-bold)}
.mainnav a[aria-current="page"]::after{content:"";position:absolute;left:50%;bottom:4px;width:16px;height:3px;margin-left:-8px;border-radius:var(--r-pill);background:var(--accent)}
.more{position:relative}
.more-panel{display:none;position:absolute;z-index:90;top:calc(100% + 10px);left:-8px;width:300px;padding:10px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--shadow-panel)}
.more.is-open .more-panel{display:block}
.more-group+.more-group{margin-top:6px;padding-top:6px;border-top:1px solid var(--border-soft)}
.more-label{padding:6px 10px 4px;font-size:11.5px;font-weight:var(--weight-bold);letter-spacing:.08em;color:var(--muted)}
.more-panel a{display:flex;flex-direction:column;align-items:flex-start;gap:0;padding:8px 10px;border-radius:var(--r-sm);color:var(--ink);font-weight:var(--weight-semibold)}
.more-panel a:hover{background:var(--panel-soft)}
.more-panel a span{font-size:12.5px;font-weight:var(--weight-normal);color:var(--muted)}
.topbar-end{margin-left:auto;display:flex;align-items:center;gap:12px;flex-shrink:0}
.lang-switch{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;min-height:40px;padding:8px 12px;border-radius:var(--r-pill);font-size:var(--text-sm);font-weight:var(--weight-medium);color:var(--muted);white-space:nowrap}
.lang span{white-space:nowrap}
.lang:hover{background:var(--panel);color:var(--ink)}
.lang-caret{font-size:11px;color:var(--muted)}
.lang-panel{display:none;position:absolute;right:0;top:calc(100% + 12px);z-index:95;width:190px;padding:8px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--panel);box-shadow:var(--shadow-panel)}
.lang-switch.is-open .lang-panel{display:block}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-sm)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--panel-2)}
.bar-sep{width:1px;height:22px;background:var(--border)}
.login{display:inline-flex;align-items:center;justify-content:center;min-height:42px;padding:8px 22px;border-radius:var(--r-button);background:var(--ink);color:var(--on-accent);font-size:15px;font-weight:var(--weight-bold);white-space:nowrap;box-shadow:inset 0 1px 0 var(--frame-hi),0 8px 18px -10px var(--sh-warm)}
.login:hover{background:var(--accent-dark)}
.hamburger{display:none;min-width:44px;min-height:44px;align-items:center;justify-content:center;flex-direction:column;gap:4px;border:1px solid var(--border);border-radius:var(--r-sm)}
.hamburger-line{display:block;width:20px;height:2px;background:currentColor}
.nav-drawer{display:none;position:fixed;z-index:82;top:var(--header-height);right:0;left:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;padding:20px var(--gutter) 40px;background:var(--panel)}
.nav-drawer a{display:flex;width:100%;align-items:center;min-height:46px;padding:11px 14px;border-radius:var(--r-sm);font-weight:var(--weight-semibold)}
.nav-drawer a:hover,.nav-drawer a[aria-current="page"]{background:var(--panel-2)}
.drawer-languages{margin-top:20px;padding-top:16px;border-top:1px solid var(--border)}
.drawer-label{padding:8px 14px;color:var(--muted);font-size:var(--text-sm)}
.nav-veil{display:none;position:fixed;z-index:81;inset:var(--header-height) 0 0;background:var(--veil)}
html.nav-open{overflow:hidden}
.site-footer{padding-top:56px;padding-bottom:28px;background:var(--panel-2);border-top:1px solid var(--border)}
.footer-grid{display:grid;grid-template-columns:minmax(0,1.2fr) minmax(0,1fr) minmax(0,1fr);gap:48px}
.footer-brand p{max-width:360px;margin-top:16px;color:var(--muted);font-size:var(--text-sm)}
.footer-title{font-size:var(--text-base);font-weight:var(--weight-bold);margin-bottom:12px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 18px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px;padding-block:4px;font-size:var(--text-sm);color:var(--muted)}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent-dark);text-decoration:underline}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;margin-top:32px;padding-top:24px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:16px;margin-top:24px;color:var(--muted);font-size:var(--text-sm)}
.footer-legal{display:flex;gap:24px}
.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:160px;max-width:100%;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:32px}
@media(max-width:1200px){
  :root{--gutter:32px;--display-size:58px}
  .topbar-in{gap:24px}
  .mainnav a,.more-btn{padding-inline:10px;font-size:var(--text-sm)}
  .brand-zh{display:none}
}
@media(max-width:1024px){
  .topbar-in{gap:20px}
  .mainnav{display:none}
  .topbar-end{margin-left:auto}
  .hamburger{display:flex}
  html.nav-open .nav-drawer,html.nav-open .nav-veil{display:block}
  .footer-grid{gap:28px}
}
@media(max-width:768px){
  :root{--display-size:40px;--heading-size:30px}
  .section{padding-top:48px;padding-bottom:48px}
  .grid-three{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:minmax(0,1fr) minmax(0,1fr)}
  .footer-brand{grid-column:1/-1}
}
@media(max-width:640px){
  :root{--gutter:20px;--header-height:64px;--anchor-offset:80px;--toc-offset:148px}
  .no-break{white-space:normal}
  .tilt,.device-tilt,[data-tilt]{transform:none}
  .grid-two{grid-template-columns:minmax(0,1fr)}
  .topbar-in{gap:8px}
  .topbar-end{gap:5px;margin-left:auto}
  .brand{gap:6px}
  .brand-mark{width:28px;height:28px}
  .brand-word{font-size:18px}
  .lang{padding-inline:6px;font-size:12px;gap:3px}
  .bar-sep{display:none}
  .login{padding-inline:12px;font-size:var(--text-sm)}
  .panel,.card{padding:20px}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .footer-links{gap:4px 16px}
  .footer-bottom{flex-direction:column}
  .hero,.device,.hero-bg,.hero-glow{max-width:100%}
}
@media(max-width:359px){
  :root{--gutter:16px;--display-size:36px}
  .brand-word{font-size:16px}
  .brand-mark{width:24px;height:24px}
  .lang{font-size:11px;padding-inline:3px}
  .login{padding-inline:9px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:0s!important;animation:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}