:root{
  --bg:#F5EFE3;--bg-top:#FAF6EE;--bg-bottom:#EFE6D6;
  --panel:#FCF9F2;--panel-bar:#F4EEE3;--panel-mid:#F8F3EA;--panel-side:#F3EDE2;
  --panel-2:#ECE3D2;--panel-2-edge:#E2D7C3;
  --border:#DED2BE;--border-strong:#CDBFA8;--hairline-dark:#4A3A2C;
  --accent:#B4462B;--accent-dark:#8C3320;--accent-soft:#D9743F;
  --accent-wash:rgba(180,70,43,.08);--on-accent:#FFF8F1;
  --text:#2A211A;--text-soft:#4A3D31;--text-muted:#6E6052;--text-faint:#978775;
  --success:#3F7D4E;--success-wash:rgba(63,125,78,.16);--warn:#A87414;--error:#9E2A2B;
  --shadow-terra:rgba(180,70,43,.10);--shadow-terra-mid:rgba(180,70,43,.14);
  --shadow-terra-strong:rgba(180,70,43,.22);--shadow-ink:rgba(42,33,26,.08);
  --shadow-ink-soft:rgba(42,33,26,.05);--highlight:rgba(255,255,255,.8);
  --chrome-close:#D5806C;--chrome-min:#D8AE5E;--chrome-max:#8EAD79;--chrome-ring:rgba(42,33,26,.14);
  --flag-red:#C8372D;--flag-blue:#2E3E6E;--flag-white:#FBF8F2;--flag-edge:rgba(42,33,26,.16);
  --paint-mauve:#A69AA3;--paint-rose:#C8A99E;--paint-amber:#DFA96C;--paint-glow:#F2CF97;
  --paint-haze:#B49F98;--paint-olive:#77714A;--paint-olive-deep:#545135;
  --paint-slate:#727986;--paint-slate-deep:#535967;
  --paint-water-light:#B9C0C2;--paint-water:#8E9CA8;--paint-water-deep:#66737F;
  --paint-shore:#6F5E4A;--paint-light:#F4E4C8;--paint-dark:#4B5562;
  --paint-shimmer:rgba(255,238,210,.42);--paint-vignette:rgba(70,44,24,.42);
  --paint-rim:rgba(60,38,22,.22);--paint-rim-hi:rgba(255,240,215,.35);
  --veil:rgba(42,33,26,.28);--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,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,"Liberation Mono",monospace;
  --r-xs:4px;--r-sm:6px;--r-md:8px;--r-lg:10px;--r-btn:7px;--r-route:5px;--r-pill:999px;--r-round:50%;
  --gutter:24px;--content:1248px;--header-height:60px;--anchor-gap:84px;--chapter-gap:148px;
  --font-size:17px;--display-size:64px;--weight-normal:400;--weight-medium:500;--weight-strong:600;
  --shadow-card:inset 0 1px 0 var(--highlight),0 1px 2px var(--shadow-ink),0 14px 36px var(--shadow-terra);
  --ease: .2s ease;--paper-texture:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='p'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' seed='5' stitchTiles='stitch'/%3E%3C/filter%3E%3Cpath filter='url(%23p)' opacity='.03' d='M0 0h160v160H0z'/%3E%3C/svg%3E");
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-gap);scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--font-size);line-height:1.6;-webkit-font-smoothing:antialiased;background-image:var(--paper-texture)}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
img{max-width:100%;height:auto}
svg{flex-shrink:0}
a{color:var(--accent);text-underline-offset:3px}
a:hover{color:var(--accent-dark)}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent-soft);outline-offset:3px}
[hidden]{display:none!important}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:var(--weight-normal);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,5vw,68px);line-height:1.12;letter-spacing:-.02em}
h2{font-size:32px;line-height:1.25;letter-spacing:-.02em}
h3{font-size:22px;line-height:1.35}
p{margin-top:0}
strong,b{font-weight:var(--weight-strong)}
code{font-family:var(--font-mono);font-size:.88em;overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--panel-2);border:1px solid var(--border);border-radius:var(--r-sm)}
pre code{overflow-wrap:normal;white-space:pre}
.no-break{white-space:nowrap}
.num{font-family:var(--font-mono);letter-spacing:-.01em;font-variant-numeric:tabular-nums}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.wrap{width:100%;max-width:var(--content);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.section{padding-top:64px;padding-bottom:64px}
.reading-wrap{max-width:860px;margin-inline:auto;min-width:0}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol{margin-bottom:24px}
.prose h2{margin-top:48px}
.prose li+li{margin-top:8px}
.prose section{min-width:0}
.prose blockquote{margin-inline:0}
.muted{color:var(--text-muted)}
.kicker{font-size:13px;letter-spacing:.04em;color:var(--text-muted)}
.card,.panel{min-width:0;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-md);padding:24px;box-shadow:var(--shadow-card)}
.panel-recessed{background:var(--panel-2)}
.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}
.card-grid>*{min-width:0}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:46px;padding:12px 24px;border:1px solid var(--clear);border-radius:var(--r-btn);font-size:16px;font-weight:var(--weight-medium);font-family:var(--font-body);text-decoration:none;line-height:1.25;white-space:nowrap;flex-shrink:0;transition:background-color var(--ease),color var(--ease),box-shadow var(--ease)}
.btn-primary{background:var(--accent);color:var(--on-accent);box-shadow:inset 0 1px 0 var(--paint-rim-hi),0 1px 2px var(--shadow-ink),0 10px 24px var(--shadow-terra-strong)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--accent-dark);color:var(--on-accent)}
.btn-primary:active{box-shadow:inset 0 2px 4px var(--shadow-ink)}
.btn-ghost,.btn-secondary{background:var(--panel-2);color:var(--text);border:1px solid var(--panel-2-edge)}
.btn-ghost:hover,.btn-secondary:hover{color:var(--accent)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);color:var(--text-muted);border-color:var(--border);box-shadow:none;cursor:not-allowed}
.btn-small{min-height:36px;padding:8px 14px;font-size:14px}
.cta-row{margin-top:24px;display:flex;justify-content:center;flex-wrap:wrap;gap:12px}
.badge{display:inline-flex;align-items:center;gap:8px;max-width:100%;margin:0;padding:5px 13px 5px 11px;border-radius:var(--r-pill);background:var(--panel);border:1px solid var(--border);font-size:13px;line-height:18px;color:var(--text-muted);box-shadow:inset 0 1px 0 var(--highlight),0 4px 12px var(--shadow-terra)}
.badge-dot,.status-dot{width:7px;height:7px;border-radius:var(--r-round);background:var(--success);box-shadow:0 0 0 3px var(--success-wash);flex-shrink:0}
.tag,.fact-chip{display:inline-flex;align-items:center;max-width:100%;padding:4px 8px;border-radius:var(--r-route);background:var(--panel-2);border:1px solid var(--panel-2-edge);font-size:12px;line-height:1.4;color:var(--text-soft);overflow-wrap:anywhere}
.fact-list{display:flex;flex-wrap:wrap;gap:8px;margin-top:20px}
.page{position:relative;overflow-x:clip;max-width:100%;background:linear-gradient(180deg,var(--bg-top) 0%,var(--bg-bottom) 84%,var(--bg) 100%);background-image:var(--paper-texture),linear-gradient(180deg,var(--bg-top) 0%,var(--bg-bottom) 84%,var(--bg) 100%)}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.paper-grain{position:absolute;inset:0;width:100%;height:100%;pointer-events:none;z-index:0;opacity:.03;mix-blend-mode:multiply}
#site-header{position:relative;z-index:50;min-height:var(--header-height)}
.topbar{position:relative;z-index:52;max-width:var(--content);height:var(--header-height);margin:0 auto;padding:0 var(--gutter);display:flex;align-items:center;gap:28px}
.brand{display:flex;align-items:center;gap:10px;color:var(--text);text-decoration:none;flex-shrink:0}
.brand-mark{display:block;width:28px;height:28px;flex-shrink:0;filter:drop-shadow(0 2px 4px var(--shadow-terra))}
.brand-en{font-family:var(--font-display);font-size:17px;font-weight:var(--weight-strong);letter-spacing:-.015em}
.brand-zh{font-size:13px;font-weight:var(--weight-normal);color:var(--text-muted);padding-left:10px;border-left:1px solid var(--border);line-height:16px}
.nav{flex:1;display:flex;justify-content:center;min-width:0}
.nav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;white-space:nowrap}
.nav li{display:flex;align-items:center}
.nav li+li::before{content:"·";margin:0 10px;color:var(--text-faint)}
.nav a{display:inline-flex;align-items:center;min-height:28px;font-size:14px;color:var(--text-muted);text-decoration:none;padding:4px 2px;border-radius:var(--r-xs);transition:color var(--ease)}
.nav a:hover{color:var(--accent)}
.nav a[aria-current="page"]{color:var(--text);font-weight:var(--weight-medium)}
.top-actions{display:flex;align-items:center;gap:10px;flex-shrink:0}
.language{position:relative}
.lang{appearance:none;display:inline-flex;align-items:center;justify-content:center;gap:4px;min-width:44px;min-height:34px;width:auto;border:0;background:var(--clear);font:inherit;font-size:13px;color:var(--text-muted);padding:6px 8px;border-radius:var(--r-xs);cursor:pointer;white-space:nowrap}
.lang:hover{color:var(--accent)}
.lang-panel{position:absolute;right:0;top:calc(100% + 8px);z-index:60;min-width:160px;padding:6px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-sm);box-shadow:var(--shadow-card)}
.lang-panel a{display:flex;align-items:center;min-height:40px;padding:8px 12px;color:var(--text);text-decoration:none;font-size:14px;border-radius:var(--r-xs)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--panel-2)}
.login{display:inline-flex;align-items:center;justify-content:center;min-height:34px;padding:6px 16px;border-radius:var(--r-sm);border:1px solid var(--border-strong);background:var(--panel);color:var(--text);font-size:14px;font-weight:var(--weight-medium);text-decoration:none;white-space:nowrap;box-shadow:inset 0 1px 0 var(--highlight),0 1px 2px var(--shadow-ink);transition:color var(--ease),border-color var(--ease)}
.login:hover{color:var(--accent);border-color:var(--accent)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:10px;border:1px solid var(--border);border-radius:var(--r-sm);background:var(--panel);color:var(--text)}
.menu-icon{width:20px;height:20px;display:flex;flex-direction:column;justify-content:center;gap:4px}
.menu-line{display:block;width:20px;height:2px;background:currentColor;border-radius:var(--r-xs)}
.nav-drawer{display:none}
.nav-veil{position:fixed;inset:var(--header-height) 0 0;z-index:48;border:0;background:var(--veil);width:100%}
html.nav-open{overflow:hidden}
.site-footer{position:relative;border-top:1px solid var(--border);background:var(--panel-2);padding-top:48px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-brand p{max-width:350px;margin:16px 0;color:var(--text-muted);font-size:14px}
.footer-heading{margin:0 0 12px;font-size:14px;font-weight:var(--weight-medium)}
.footer-links{display:flex;flex-wrap:wrap;gap:4px 16px;list-style:none;padding:0;margin:0}
.footer-links a,.footer-languages a,.footer-bottom a{display:inline-flex;align-items:center;min-height:28px;font-size:13px;color:var(--text-muted);text-decoration:none}
.footer-links a:hover,.footer-languages a:hover,.footer-bottom a:hover{color:var(--accent)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;border-top:1px solid var(--border);margin-top:32px;padding-top:20px}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px;margin-top:16px;color:var(--text-muted);font-size:13px}
.footer-legal{display:flex;gap:20px}
.reveal{transition:opacity .35s ease,transform .35s ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:120px;max-width:100%;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:24px}
#server-status>*{min-width:0;max-width:100%}
@media(max-width:1200px){
  .topbar{gap:16px}.nav li+li::before{margin-inline:6px}.nav a{font-size:13px}
}
@media(max-width:1100px){
  .top-actions{gap:6px}.lang{padding-inline:4px}
}
@media(max-width:960px){
  #site-header{background:var(--bg-top)}
  .topbar{flex-wrap:nowrap;gap:12px}
  .nav{display:none}
  .top-actions{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .nav-drawer{position:fixed;inset:var(--header-height) 0 auto;z-index:51;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--panel);padding:16px var(--gutter) 40px}
  .nav-drawer:not([hidden]){display:block}
  .nav-drawer a{display:flex;align-items:center;min-height:46px;width:100%;padding:11px 12px;border-bottom:1px solid var(--border);text-decoration:none;color:var(--text)}
  .nav-drawer a[aria-current="page"]{color:var(--accent);background:var(--accent-wash)}
  .drawer-languages{margin-top:20px;border-top:1px solid var(--border)}
  .card-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media(max-width:768px){
  h1{font-size:clamp(28px,8.6vw,40px)}
  h2{font-size:28px}
  .section{padding-top:40px;padding-bottom:40px}
  .footer-grid{grid-template-columns:1fr;gap:28px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,.float-refund{transform:none}
  .topbar{gap:8px}
  .brand{gap:6px}.brand-mark{width:25px;height:25px}.brand-en{font-size:15px}
  .brand-zh{font-size:12px}
  .top-actions{gap:4px;margin-left:auto}
  .lang{font-size:12px;padding-inline:4px}
  .login{padding-inline:10px;font-size:13px}
  .card-grid{grid-template-columns:minmax(0,1fr)}
  .card,.panel{padding:20px}
  .btn{min-height:44px;padding-inline:18px;font-size:15px}
  .page,.decorated{overflow-x:clip;max-width:100%}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
  *,*::before,*::after{animation:none!important;transition:none!important}
}