:root{
  --bg:#F5EEE1;--bg-panel:#FFFCF6;--bg-panel-2:#EFE5D3;--border:#E2D6C1;--border-soft:#ECE2D1;
  --accent:#4A3CC2;--accent-dark:#33298F;--accent-2:#6E5CE6;--text:#2A2118;--text-muted:#6E6255;--text-faint:#918473;
  --success:#2F8A52;--warn:#B9730F;--error:#C2412D;
  --hero-top:#FAF5EC;--hero-bottom:#EFE5D3;--board-a:#E9DFCF;--board-b:#D8D2E6;--iris-tint:#ECE8FA;--iris-line:#D3CBF4;--apricot:#F7E5CE;
  --on-accent:#FFFFFF;--on-dark:#F5EEE1;--on-dark-dim:rgba(245,238,225,.14);
  --shadow-iris:rgba(74,60,194,.12);--shadow-iris-2:rgba(74,60,194,.20);--shadow-cta:rgba(74,60,194,.55);
  --shadow-warm:rgba(42,33,24,.06);--shadow-dark:rgba(42,33,24,.38);
  --glow-near:rgba(110,92,230,.14);--glow-far:rgba(110,92,230,.30);
  --hl-strong:rgba(255,255,255,.82);--hl-soft:rgba(255,255,255,.42);--hl-sheen:rgba(255,255,255,.46);
  --board-edge:rgba(42,33,24,.06);--lens-glass:rgba(110,92,230,.07);--clear:transparent;
  --flag-red:#C8323A;--flag-blue:#253A7A;--flag-white:#FFFFFF;--flag-edge:rgba(42,33,24,.16);
  --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;
  --weight-body:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-display:900;
  --r-xs:6px;--r-sm:8px;--r-md:10px;--r-lg:12px;--r-board:18px;--r-pill:999px;--r-circle:50%;--r-bubble:9px;--r-tail:3px;--r-handle:4px;
  --container:1344px;--reading:800px;--gutter:32px;--header-height:68px;--toc-offset:16px;--anchor-offset:100px;
  --text-base:16px;--text-small:14px;--title-size:clamp(52px,4.6vw,66px);--heading-size:clamp(28px,3.2vw,40px);
  --tracking-display:-.03em;--tracking-cjk:-.02em;
  --space-section:80px;--ease:cubic-bezier(.2,.7,.3,1);--duration:.35s;
  --panel-shadow:inset 0 1px 0 var(--hl-strong),0 24px 54px -30px var(--shadow-iris);
  --grain:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='160' height='160'%3E%3Cfilter id='g'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 .16 0 0 0 0 .13 0 0 0 0 .09 .12 0 0 0 -.03'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23g)'/%3E%3C/svg%3E");
}
*,*::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(--text);font-family:var(--font-body);font-size:var(--text-base);font-weight:var(--weight-body);line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
body::before{content:"";position:fixed;inset:0;background-image:var(--grain);pointer-events:none;z-index:100}
[hidden]{display:none!important}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
img{display:block;max-width:100%;height:auto}
svg{display:block;flex-shrink:0}
p{margin:0 0 1.25em}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:var(--weight-display);overflow-wrap:break-word;text-wrap:balance}
h1{font-size:var(--title-size);line-height:1.1;letter-spacing:var(--tracking-display)}
h2{font-size:var(--heading-size);line-height:1.2;letter-spacing:var(--tracking-display)}
h3{font-size:24px;line-height:1.35}
:lang(zh-CN) h1,:lang(zh-CN) h2,:lang(zh-TW) h1,:lang(zh-TW) h2{letter-spacing:var(--tracking-cjk)}
::selection{background:var(--iris-tint);color:var(--accent-dark)}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px;border-radius:var(--r-xs)}
.container,.wrap{width:100%;max-width:var(--container);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:var(--reading);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:var(--space-section);padding-bottom:var(--space-section)}
.section-head{max-width:780px;margin:0 auto 32px;text-align:center}
.section-head h2{margin:16px 0}
.section-head p{color:var(--text-muted)}
.grid{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>*{min-width:0}
.no-break{white-space:nowrap}
.visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.panel,.card{min-width:0;padding:24px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--panel-shadow)}
.inset-panel{padding:20px;border-radius:var(--r-md);background:var(--bg-panel-2)}
.decoration-zone{position:relative;overflow-x:clip;max-width:100%}
.prose{min-width:0;overflow-wrap:break-word}
.prose h2{margin-top:2em}
.prose h3{margin-top:1.6em}
.prose a:not(.btn){text-decoration:underline;text-underline-offset:3px;color:var(--accent)}
.prose li+li{margin-top:8px}
code{font-family:var(--font-mono);font-size:.9em;overflow-wrap:anywhere;background:var(--bg-panel-2);border-radius:var(--r-xs);padding:2px 5px}
pre{max-width:100%;overflow-x:auto;padding:20px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--bg-panel)}
pre code{background:var(--clear);padding:0;overflow-wrap:normal;white-space:pre}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:52px;padding:10px 24px;border:1px solid var(--clear);border-radius:var(--r-md);font-size:16px;font-weight:var(--weight-bold);line-height:1.4;white-space:nowrap;flex-shrink:0;text-decoration:none}
.btn svg{width:18px;height:18px}
.btn-primary{background:var(--accent);color:var(--on-accent);box-shadow:inset 0 1px 0 var(--hl-soft),0 14px 26px -14px var(--shadow-cta)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--accent-dark)}
.btn-ghost,.btn-secondary{background:var(--bg-panel);color:var(--text);border-color:var(--border);box-shadow:inset 0 1px 0 var(--hl-strong),0 2px 6px -3px var(--shadow-warm)}
.btn-ghost:hover,.btn-secondary:hover{border-color:var(--text-muted)}
.btn:active,.btn.is-active{transform:translateY(1px)}
.btn:disabled{background:var(--bg-panel-2);color:var(--text-muted);border-color:var(--border);box-shadow:none}
.btn-small{min-height:40px;padding:8px 16px;font-size:14px}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin-top:32px}
.notice{background:var(--text);color:var(--on-dark);font-size:13.5px;line-height:1.4}
.notice .container{display:flex;justify-content:center;align-items:center;gap:10px;min-height:40px;padding-block:8px}
.notice-bolt{font-size:14px;flex-shrink:0}
.notice a{font-weight:var(--weight-semibold);text-decoration:underline;text-underline-offset:3px;min-height:24px;display:inline-flex;align-items:center;white-space:nowrap}
.notice a:hover{color:var(--bg-panel)}
.site-header{position:relative;z-index:50;background:var(--hero-top);border-bottom:1px solid var(--border-soft)}
.header-row,.site-header>.container{display:flex;align-items:center;gap:24px;min-height:var(--header-height);flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0;min-height:40px}
.brand-logo{width:32px;height:32px;flex-shrink:0}
.brand-en{font-family:var(--font-display);font-weight:var(--weight-display);font-size:19px;letter-spacing:var(--tracking-cjk)}
.brand-zh{font-size:13.5px;font-weight:var(--weight-medium);color:var(--text-muted);padding-left:10px;border-left:1px solid var(--border)}
.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;gap:2px}
.nav a{display:flex;align-items:center;gap:6px;min-height:36px;padding:6px 10px;border-radius:var(--r-sm);font-size:14px;font-weight:var(--weight-medium);white-space:nowrap}
.nav a svg{width:16px;height:16px;color:var(--text-muted)}
.nav a:hover{background:var(--bg-panel-2)}
.nav a[aria-current="page"]{background:var(--iris-tint);color:var(--accent);font-weight:var(--weight-semibold)}
.nav a[aria-current="page"] svg{color:var(--accent)}
.header-actions{display:flex;align-items:center;gap:8px;flex-shrink:0;margin-left:auto}
.language{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;min-height:36px;padding:6px 10px;border:0;border-radius:var(--r-sm);background:var(--clear);font-size:14px;color:var(--text-muted)}
.lang span{white-space:nowrap}
.lang svg{width:16px;height:16px}
.lang:hover{background:var(--bg-panel-2);color:var(--text)}
.lang-panel{position:absolute;right:0;top:calc(100% + 10px);z-index:70;min-width:180px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:var(--panel-shadow)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-sm);white-space:nowrap}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--iris-tint);color:var(--accent)}
.btn-login{display:inline-flex;align-items:center;justify-content:center;gap:7px;min-height:38px;padding:8px 16px;border-radius:var(--r-sm);background:var(--text);color:var(--on-dark);font-size:14px;font-weight:var(--weight-semibold);white-space:nowrap;box-shadow:inset 0 1px 0 var(--on-dark-dim),0 6px 14px -8px var(--shadow-dark)}
.btn-login svg{width:15px;height:15px}
.btn-login:hover{background:var(--accent-dark)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;background:var(--clear);border:1px solid var(--border);border-radius:var(--r-sm)}
.menu-toggle svg{width:22px;height:22px}
.mobile-drawer{display:none}
html.nav-open{overflow:hidden}
.site-footer{padding-top:56px;padding-bottom:32px;background:var(--bg-panel-2);border-top:1px solid var(--border)}
.footer-grid{display:grid;grid-template-columns:1.15fr 1fr 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-brand p{margin-top:16px;max-width:29em;color:var(--text-muted);font-size:14px}
.footer-title{margin:0 0 12px;font-size:16px;font-weight:var(--weight-bold)}
.footer-links{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 16px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px;font-size:14px}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent);text-decoration:underline;text-underline-offset:3px}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:28px}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:16px;margin-top:24px;padding-top:24px;border-top:1px solid var(--border);font-size:13px;color:var(--text-muted)}
.footer-bottom p{margin:0}
.footer-legal{display:flex;flex-wrap:wrap;gap:16px}
.reveal{transition:opacity var(--duration) var(--ease),transform var(--duration) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:static;display:block;min-width:0;max-width:100%;min-height:80px;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:24px}
@media(min-width:1101px) and (max-width:1260px){.nav a{padding-inline:8px}.header-row,.site-header>.container{gap:16px}}
@media(max-width:1100px){
  .nav{display:none}
  .header-actions{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .mobile-drawer{position:fixed;top:var(--drawer-top,var(--header-height));left:0;right:0;z-index:45;height:calc(100dvh - var(--drawer-top,var(--header-height)));max-height:calc(100dvh - var(--drawer-top,var(--header-height)));overflow-y:auto;overscroll-behavior:contain;background:var(--bg-panel);padding:16px var(--gutter) 32px;border-top:1px solid var(--border)}
  .mobile-drawer:not([hidden]){display:block}
  .mobile-drawer ul{list-style:none;margin:0;padding:0}
  .mobile-drawer a{display:flex;align-items:center;gap:12px;width:100%;min-height:46px;padding:11px 12px;border-radius:var(--r-sm)}
  .mobile-drawer a svg{width:18px;height:18px;color:var(--accent)}
  .mobile-drawer a:hover,.mobile-drawer a[aria-current]{background:var(--iris-tint);color:var(--accent)}
  .drawer-languages{margin-top:20px;padding-top:16px;border-top:1px solid var(--border)}
}
@media(max-width:768px){
  h1{font-size:clamp(28px,7vw,40px)}
  .grid-3{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
}
@media(max-width:640px){
  :root{--gutter:18px;--space-section:48px}
  .no-break{white-space:normal}
  .grid-2{grid-template-columns:minmax(0,1fr)}
  .header-row,.site-header>.container{gap:8px}
  .header-actions{gap:4px;margin-left:auto}
  .brand{gap:6px}.brand-en{font-size:17px}.brand-logo{width:28px;height:28px}.brand-zh{display:none}
  .lang{padding-inline:6px;font-size:12px;gap:4px}
  .lang svg{display:none}
  .btn-login{padding-inline:10px;font-size:13px}
  .btn-login svg{display:none}
  .notice{font-size:12px}.notice .container{gap:6px;flex-wrap:wrap}
  .tilt,.tilt-card{transform:none}
  .decoration-zone{max-width:100%;overflow-x:clip}
  .footer-links{gap:6px 14px}
  .panel,.card{padding:20px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}