:root{
  --bg:#F5EDDD;--bg-top:#FBF6EC;--bg-bottom:#EFE4D0;
  --panel:#FCF8F0;--panel-2:#EFE4D0;--border:#E2D5BE;
  --accent:#1D4F9C;--accent-dark:#12346B;--text:#2A2119;--muted:#6B5D4D;
  --success:#2E7D4F;--warn:#B7791F;--error:#B3392F;
  --peach:#E9876A;--peach-soft:#F3B49A;--ice:#CFE6F2;--white:#FFFFFF;
  --bar:#3A2F26;--bar-label:#2A2119;--bar-text:#E8DCC8;
  --accent-a08:rgba(29,79,156,.08);--accent-a10:rgba(29,79,156,.10);--accent-a12:rgba(29,79,156,.12);--accent-a16:rgba(29,79,156,.16);--accent-a24:rgba(29,79,156,.24);--accent-a35:rgba(29,79,156,.35);
  --ink-a03:rgba(42,33,25,.03);--ink-a06:rgba(42,33,25,.06);--ink-a10:rgba(42,33,25,.10);--ink-a16:rgba(42,33,25,.16);--ink-a35:rgba(42,33,25,.35);
  --success-a25:rgba(46,125,79,.28);--hl:rgba(255,255,255,.80);--hl-soft:rgba(255,255,255,.45);--hl-btn:rgba(255,255,255,.24);--hl-faint:rgba(255,255,255,.10);
  --glass:rgba(252,248,240,.66);--glass-strong:rgba(252,248,240,.86);
  --tile-a:rgba(29,79,156,.82);--tile-b:rgba(18,52,107,.64);--tile-light:rgba(243,180,154,.66);
  --flag-red:#C8283A;--flag-blue:#22407E;--flag-green:#13855A;--flag-white:#FFFFFF;--mask:#000000;
  --font-display:'Inter','Noto Sans SC','PingFang SC','Hiragino Sans','Yu Gothic','Apple SD Gothic Neo','Malgun Gothic','Microsoft YaHei',system-ui,sans-serif;
  --font-body:'Inter','Noto Sans SC','PingFang SC','Hiragino Sans','Yu Gothic','Apple SD Gothic Neo','Malgun Gothic','Microsoft YaHei',system-ui,sans-serif;
  --font-mono:'JetBrains Mono','SFMono-Regular',Menlo,Consolas,'Liberation Mono',monospace;
  --r-xs:4px;--r-sm:6px;--r-md:10px;--r-pill:999px;--r-round:50%;
  --gutter:40px;--content-width:1280px;--header-height:64px;--anchor-offset:80px;--toc-offset:144px;
  --size-display:66px;--size-h2:36px;--size-h3:23px;--size-body:16px;--size-small:14px;
  --weight-display:800;--weight-strong:650;--tracking-display:-.03em;--tracking-cjk:-.02em;
  --shadow-panel:inset 0 1px 0 var(--hl),0 24px 50px -32px var(--accent-a24);
  --shadow-glass:inset 0 0 0 1px var(--hl),0 0 0 1px var(--ink-a06),0 26px 50px -24px var(--accent-a24);
  --grain-opacity:.03;--ease-ui:cubic-bezier(.2,.7,.2,1);--duration-ui:.22s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
body{margin:0;min-height:100vh;font-family:var(--font-body);font-size:var(--size-body);line-height:1.7;color:var(--text);background:linear-gradient(180deg,var(--bg-top) 0,var(--bg) 520px,var(--bg-bottom) 900px,var(--bg) 1400px) no-repeat,var(--bg);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
body::before{content:"";position:fixed;inset:0;z-index:0;pointer-events:none;opacity:var(--grain-opacity);background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='p'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Cpath filter='url(%23p)' opacity='.6' d='M0 0h180v180H0z'/%3E%3C/svg%3E");mix-blend-mode:multiply}
body>header,body>main,body>footer,.page{position:relative;z-index:1}
img,svg{vertical-align:middle}
img{display:block;max-width:100%;height:auto}
button,input,select,textarea{font:inherit}
button,a,summary{-webkit-tap-highlight-color:var(--accent-a12)}
button{cursor:pointer}
button:disabled,.btn[aria-disabled="true"]{cursor:not-allowed;opacity:.5}
a{color:var(--accent);text-underline-offset:3px}
a:hover{color:var(--accent-dark)}
a,button,summary{touch-action:manipulation}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
button{border:0}
[hidden]{display:none!important}
h1,h2,h3{font-family:var(--font-display);font-weight:var(--weight-display);line-height:1.2;text-wrap:balance}
h1{font-size:clamp(52px,5vw,68px);letter-spacing:var(--tracking-cjk);margin:0 0 30px}
h2{font-size:var(--size-h2);letter-spacing:var(--tracking-cjk);margin:0 0 24px}
h3{font-size:var(--size-h3);letter-spacing:var(--tracking-cjk);margin:0 0 16px}
p{margin:0 0 20px}
ul,ol{padding-left:1.5em}
code{font-family:var(--font-mono);font-size:.88em;overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;background:var(--panel-2);padding:24px;border-radius:var(--r-sm)}
pre code{overflow-wrap:normal;white-space:pre}
blockquote{margin-inline:0}
hr{border:0;border-top:1px solid var(--border);margin-block:32px}
.wrap{width:100%;max-width:var(--content-width);padding-inline:var(--gutter);margin-inline:auto}
.wrap>*{min-width:0}
.section{padding-top:80px;padding-bottom:80px}
.section-heading{max-width:760px;margin-bottom:40px}
.section-heading p,.muted{color:var(--muted)}
.no-break{white-space:nowrap}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.icon{width:24px;height:24px;flex-shrink:0}
.ico-line{fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.panel,.card{min-width:0;padding:28px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--panel);box-shadow:var(--shadow-panel)}
.panel-sunken{background:var(--panel-2)}
.grid-2,.grid-3{display:grid;gap:24px}
.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-2>*,.grid-3>*{min-width:0}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:52px;padding:0 24px;border:1px solid transparent;border-radius:var(--r-sm);font:600 16px/1.2 var(--font-body);text-decoration:none;white-space:nowrap;flex-shrink:0;transition:transform var(--duration-ui) var(--ease-ui),background var(--duration-ui),color var(--duration-ui)}
.btn-solid,.btn-primary{padding-inline:30px;color:var(--white);background:var(--accent);box-shadow:inset 0 1px 0 var(--hl-btn),0 16px 30px -14px var(--accent-a35),0 2px 6px -2px var(--accent-a24)}
.btn-solid:hover,.btn-primary:hover{color:var(--white);background:var(--accent-dark);transform:translateY(-1px)}
.btn-secondary{border-color:var(--border);background:var(--panel);color:var(--text);box-shadow:inset 0 1px 0 var(--hl)}
.btn-secondary:hover{background:var(--panel-2);color:var(--text)}
.btn-arrow{padding-inline:2px;background:transparent;color:var(--text);border-color:transparent}
.arr{display:inline-block;transition:transform var(--duration-ui)}
.btn-arrow:hover .arr,.notice-link:hover .arr{transform:translateX(3px)}
.btn-small{min-height:40px;padding-inline:18px;font-size:14px}
.btn-demo-hover{background:var(--accent-dark)}
.cta-row{display:flex;align-items:center;flex-wrap:wrap;gap:28px;margin:0 0 28px}
.masthead{border-bottom:1px solid var(--ink-a10);position:relative;z-index:200}
#site-header{position:relative;z-index:200}
.masthead-row{display:flex;align-items:center;gap:28px;height:var(--header-height);flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;flex:none;color:var(--text);text-decoration:none;min-height:30px}
.brand:hover{color:var(--text)}
.brand-mark{width:30px;height:30px;flex:none}
.brand-word{font:800 20px/1 var(--font-display);letter-spacing:-.025em;white-space:nowrap}
.brand-zh{font-size:14px;font-weight:500;color:var(--muted);white-space:nowrap}
.tabs{flex:1;min-width:0}
.tabs ul{display:flex;align-items:center;justify-content:center;gap:2px;list-style:none;margin:0;padding:0}
.tabs li{min-width:0}
.tab{position:relative;display:flex;align-items:center;justify-content:center;min-height:var(--header-height);padding:0 13px;color:var(--muted);text-decoration:none;font-size:14.5px;font-weight:500;white-space:nowrap}
.tab::after{content:"";position:absolute;left:13px;right:13px;bottom:-1px;height:2px;border-radius:var(--r-pill);background:var(--accent);transform:scaleX(0);transform-origin:left center;opacity:.35;transition:transform .28s ease,opacity .28s ease}
.tab:hover{color:var(--text)}
.tab:hover::after{transform:scaleX(1)}
.tab.is-active{color:var(--text);font-weight:650}
.tab.is-active::after{transform:scaleX(1);opacity:1}
.masthead-tools{display:flex;align-items:center;gap:18px;flex-shrink:0}
.language-picker{position:relative}
.lang{appearance:none;display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;min-width:44px;width:auto;padding:8px 2px;background:transparent;color:var(--muted);font:500 14px/1 var(--font-body)}
.lang span{white-space:nowrap}
.lang svg{width:15px;height:15px;flex-shrink:0}
.lang:hover{color:var(--text)}
.language-panel{position:absolute;right:0;top:calc(100% + 12px);min-width:180px;padding:8px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-sm);box-shadow:var(--shadow-panel);z-index:90}
.language-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;color:var(--text);text-decoration:none;border-radius:var(--r-xs);white-space:nowrap}
.language-panel a:hover,.language-panel a[aria-current="true"]{background:var(--panel-2)}
.btn-login{display:inline-flex;align-items:center;justify-content:center;height:38px;min-height:38px;padding:0 20px;border-radius:var(--r-sm);background:var(--text);color:var(--panel);font:600 14px/1 var(--font-body);text-decoration:none;white-space:nowrap;box-shadow:inset 0 1px 0 var(--hl-faint),0 8px 18px -10px var(--ink-a35);transition:transform .2s ease}
.btn-login:hover{color:var(--panel);transform:translateY(-1px)}
.menu-toggle{display:none;flex-direction:column;align-items:center;justify-content:center;gap:4px;min-width:44px;min-height:44px;padding:10px;background:transparent;color:var(--text);border-radius:var(--r-sm)}
.menu-line{display:block;width:20px;height:2px;background:currentColor;flex-shrink:0;transition:transform .2s,opacity .2s}
.menu-toggle[aria-expanded="true"] .menu-line:first-child{transform:translateY(6px) rotate(45deg)}
.menu-toggle[aria-expanded="true"] .menu-line:nth-child(2){opacity:0}
.menu-toggle[aria-expanded="true"] .menu-line:last-child{transform:translateY(-6px) rotate(-45deg)}
.mobile-drawer{display:none}
.menu-veil{display:none}
html.nav-open{overflow:hidden}
.site-footer{border-top:1px solid var(--border);background:var(--panel-2);padding-top:56px;padding-bottom:28px;overflow-x:clip}
.footer-grid{display:grid;grid-template-columns:1.1fr 1fr 1fr;gap:48px}
.footer-brand p{max-width:27em;color:var(--muted);font-size:14px;margin-top:18px}
.footer-heading{font-size:15px;margin-bottom:16px;letter-spacing:0}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 18px;list-style:none;margin:0;padding:0}
.footer-links a{display:inline-flex;align-items:center;min-height:32px;color:var(--muted);text-decoration:none;font-size:14px}
.footer-links a:hover{color:var(--text);text-decoration:underline}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;margin-top:32px}
.footer-languages a{display:inline-flex;align-items:center;min-height:32px;font-size:14px;color:var(--text)}
.footer-bottom{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:16px;margin-top:24px;padding-top:24px;border-top:1px solid var(--border);font-size:13px;color:var(--muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:16px}
.footer-legal a{display:inline-flex;align-items:center;min-height:28px;color:var(--muted)}
.reveal{transition:opacity .35s ease,transform .35s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
.prose{max-width:800px;margin-inline:auto;overflow-wrap:break-word}
.prose h2{margin-top:56px}
.prose h3{margin-top:32px}
.prose p,.prose li{line-height:1.85}
.prose img{border-radius:var(--r-sm)}
#server-status{position:relative;display:block;min-width:0;min-height:80px;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:32px}
[data-counter]{display:inline-block;min-width:3ch;font-family:var(--font-mono);font-variant-numeric:tabular-nums;text-align:right}
@media(min-width:1101px) and (max-width:1320px){
  .masthead-row{gap:18px}.tab{padding-inline:9px}.tabs ul{gap:3px}.masthead-tools{gap:12px}
}
@media(max-width:1100px){
  .masthead-row{gap:16px}
  .tabs{display:none}
  .masthead-tools{margin-left:auto}
  .menu-toggle{display:flex}
  .mobile-drawer{position:fixed;top:var(--header-height);left:0;right:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;z-index:55;background:var(--panel);padding:20px var(--gutter) 32px}
  .mobile-drawer:not([hidden]){display:block}
  .mobile-drawer ul{list-style:none;padding:0;margin:0}
  .mobile-drawer a{display:flex;width:100%;align-items:center;min-height:48px;padding:12px 16px;text-decoration:none;color:var(--text);border-radius:var(--r-xs)}
  .mobile-drawer a.is-active{background:var(--panel-2);box-shadow:inset 2px 0 var(--accent)}
  .drawer-languages{border-top:1px solid var(--border);padding-top:16px;margin-top:16px}
  .drawer-languages a{font-size:14px}
  .menu-veil{position:fixed;top:var(--header-height);left:0;right:0;bottom:0;background:var(--ink-a35);z-index:50}
  .menu-veil:not([hidden]){display:block}
}
@media(max-width:768px){
  :root{--gutter:20px;--size-h2:28px;--size-h3:21px}
  h1{font-size:clamp(28px,9vw,40px)}
  .section{padding-top:56px;padding-bottom:56px}
  .grid-3{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
  .footer-brand{grid-column:1/-1}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .grid-2{grid-template-columns:1fr}
  .masthead-row{gap:8px}
  .masthead-tools{gap:8px;margin-left:auto}
  .brand{gap:6px}.brand-word{font-size:18px}.brand-mark{width:26px;height:26px}
  .lang{font-size:12px;gap:4px}.lang svg{width:13px;height:13px}
  .btn-login{padding-inline:12px;font-size:13px}
  .menu-toggle{padding:8px}
  .card,.panel{padding:22px}
  .tilt,.tilt-card,[data-tilt]{transform:none}
  .decoration,.stripe-halo{max-width:100%}
  .cta-row{gap:16px 24px}
  .footer-grid{grid-template-columns:1fr}
  .footer-brand{grid-column:auto}
}
@media(max-width:359px){
  .masthead-tools{gap:4px}.brand-word{font-size:16px}.brand-mark{width:24px;height:24px}.lang{font-size:11px}.btn-login{padding-inline:10px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}