:root{
  --bg:#F6EFE2;
  --bg-panel:#FFFBF3;
  --bg-panel-2:#EFE5D2;
  --border:#E2D6C0;
  --border-strong:#D3C4A8;
  --ring:#DCCDB3;
  --accent:#2F6BD8;
  --accent-dark:#1E4FA8;
  --text:#2A2118;
  --text-muted:#6E6152;
  --text-soft:#8C7E6C;
  --success:#2E8A57;
  --warn:#C98A12;
  --error:#C2412F;
  --on-accent:#FFFFFF;
  --wish-cream:#FBF3D6;
  --board-top:#FBF6EC;
  --board-bottom:#F0E6D4;
  --apricot:#E9B48A;
  --spot-blue:rgba(47,107,216,.10);
  --spot-apricot:rgba(233,180,138,.09);
  --accent-08:rgba(47,107,216,.08);
  --accent-12:rgba(47,107,216,.12);
  --accent-glow:rgba(47,107,216,.38);
  --mention-bg:rgba(47,107,216,.11);
  --mention-edge:rgba(47,107,216,.22);
  --ink-04:rgba(42,33,24,.04);
  --ink-06:rgba(42,33,24,.06);
  --ink-08:rgba(42,33,24,.08);
  --ink-12:rgba(42,33,24,.12);
  --hi-edge:rgba(255,255,255,.88);
  --hi-soft:rgba(255,255,255,.28);
  --sheen:rgba(255,255,255,.06);
  --sheen-strong:rgba(255,255,255,.5);
  --veil:rgba(255,251,243,.62);
  --ring-fill:rgba(255,251,243,.42);
  --capsule-from:rgba(255,251,243,.80);
  --capsule-to:rgba(233,180,138,.24);
  --scrim:rgba(42,33,24,.24);
  --transparent:transparent;
  --grain-opacity:.04;
  --flag-red:#C8402F;
  --flag-white:#FFFDF7;
  --flag-navy:#24356B;
  --flag-black:#2A2118;
  --flag-gold:#E2B33C;
  --flag-edge:rgba(42,33,24,.16);
  --radius-sm:8px;
  --radius-md:12px;
  --radius-card:14px;
  --radius-ring:18px;
  --radius-board:28px;
  --radius-mobile-board:22px;
  --radius-capsule:20px;
  --radius-pill:999px;
  --radius-round:50%;
  --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-normal:400;
  --weight-medium:500;
  --weight-semibold:600;
  --size-body:16px;
  --size-small:14px;
  --size-h1:66px;
  --size-h2:44px;
  --size-h3:24px;
  --tracking-display:-.03em;
  --tracking-cjk:-.02em;
  --gutter:32px;
  --wrap-width:1200px;
  --reading-width:800px;
  --header-height:76px;
  --anchor-offset:92px;
  --toc-offset:156px;
  --space-1:4px;
  --space-2:8px;
  --space-3:12px;
  --space-4:16px;
  --space-5:24px;
  --space-6:32px;
  --space-7:40px;
  --space-8:48px;
  --space-9:64px;
  --space-10:96px;
  --shadow-lift:0 32px 72px -18px var(--accent-12),0 10px 24px -14px var(--ink-12);
  --shadow-float:0 14px 30px -14px var(--accent-12),0 2px 6px -2px var(--ink-08);
  --shadow-pop:0 18px 40px -16px var(--accent-12),0 4px 12px -4px var(--ink-08);
  --shadow-inset:inset 0 1px 0 var(--hi-edge);
  --ease-out:cubic-bezier(.2,.7,.2,1);
  --duration-fast:.2s;
  --duration-reveal:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{background:var(--bg);-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
body{margin:0;font-family:var(--font-body);font-size:var(--size-body);line-height:1.6;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
[hidden]{display:none!important}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
button,input,textarea,select{font:inherit}
button{cursor:pointer}
button,a,summary{-webkit-tap-highlight-color:var(--accent-08)}
button{color:inherit}
a{color:var(--accent);text-underline-offset:.2em}
:where(a,button,input,textarea,select,summary,[tabindex]):focus-visible{outline:2px solid var(--accent-dark);outline-offset:3px}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:var(--weight-normal);overflow-wrap:break-word;text-wrap:balance}
h1{font-size:clamp(52px,4.7vw,72px);line-height:1.12;letter-spacing:var(--tracking-cjk);margin:0 0 var(--space-5)}
h2{font-size:var(--size-h2);line-height:1.2;letter-spacing:var(--tracking-cjk);margin:0 0 var(--space-5)}
h3{font-size:var(--size-h3);line-height:1.35;margin:0 0 var(--space-4)}
p{margin:0 0 var(--space-4)}
strong,b{font-weight:var(--weight-semibold)}
code{font-family:var(--font-mono);overflow-wrap:anywhere}
pre{max-width:100%;min-width:0;overflow-x:auto;padding:var(--space-5);background:var(--bg-panel-2);border-radius:var(--radius-sm);font-family:var(--font-mono);font-size:13px;line-height:1.8}
pre code{overflow-wrap:normal;white-space:pre}
summary{list-style:none;cursor:pointer;min-height:24px}
summary::-webkit-details-marker{display:none}
.no-break{white-space:nowrap}
.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(--wrap-width);margin-inline:auto;padding-inline:var(--gutter)}
.reading-wrap{width:100%;max-width:var(--reading-width);margin-inline:auto;padding-inline:var(--gutter)}
.sec{padding-top:var(--space-10);padding-bottom:var(--space-10)}
.stack{display:grid;gap:var(--space-5);min-width:0}
.grid{display:grid;gap:var(--space-5);min-width:0}
.grid>* ,.stack>*{min-width:0}
.grid-three{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-five{grid-template-columns:repeat(5,minmax(0,1fr))}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono)}
.panel,.card{min-width:0;padding:var(--space-5);border:1px solid var(--border);border-radius:var(--radius-md);background:var(--bg-panel);box-shadow:var(--shadow-inset),var(--shadow-float)}
.panel-inset{background:var(--bg-panel-2);box-shadow:inset 0 1px 2px var(--ink-08)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:48px;padding:0 26px;border:1px solid var(--transparent);border-radius:var(--radius-pill);font-size:16px;font-weight:var(--weight-medium);text-decoration:none;white-space:nowrap;flex-shrink:0;transition:background-color var(--duration-fast),transform var(--duration-fast),box-shadow var(--duration-fast)}
.btn svg{width:18px;height:18px}
.btn-primary{background:var(--accent);color:var(--on-accent);box-shadow:inset 0 1px 0 var(--hi-soft),0 10px 22px -10px var(--accent-glow)}
.btn-primary:hover{background:var(--accent-dark);transform:translateY(-1px)}
.btn-ghost,.btn-secondary{background:var(--transparent);color:var(--text);border-color:var(--text)}
.btn-ghost:hover,.btn-secondary:hover{background:var(--veil)}
.btn:active{transform:translateY(0)}
.btn:disabled,.btn[aria-disabled="true"]{cursor:not-allowed;background:var(--bg-panel-2);color:var(--text-muted);border-color:var(--border-strong);box-shadow:none}
.cta-row{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin-top:28px}
#site-header{position:relative;z-index:50;min-height:var(--header-height)}
.topbar{position:relative;z-index:53;display:flex;flex-wrap:nowrap;align-items:center;gap:40px;height:var(--header-height);padding:0 48px;background:var(--bg)}
.brand{display:inline-flex;align-items:center;gap:10px;color:var(--text);text-decoration:none;flex:none;min-height:32px}
.brand-mark{display:block;width:30px;height:30px;flex:none}
.brand-en{font-size:18px;font-weight:var(--weight-semibold);letter-spacing:-.01em;line-height:1;white-space:nowrap}
.brand-zh{font-size:14px;font-weight:var(--weight-normal);color:var(--text-muted);line-height:1;padding-left:10px;border-left:1px solid var(--border-strong)}
.mainnav{flex:1;min-width:0}
.mainnav>ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:4px}
.mainnav a,.nav-more>summary,.lang>summary,.lang-button,.preview-menu>summary{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;padding:0 14px;border:0;border-radius:var(--radius-pill);background:var(--transparent);font-size:15px;color:var(--text-muted);text-decoration:none;white-space:nowrap;transition:color var(--duration-fast),background-color var(--duration-fast)}
.mainnav a:hover,.nav-more>summary:hover,.lang-button:hover{color:var(--text);background:var(--veil)}
.mainnav a[aria-current="page"],.nav-more>summary[data-current]{color:var(--text);background:var(--bg-panel-2)}
.nav-more,.lang,.preview-menu{position:relative}
.chev{width:12px;height:12px;transition:transform var(--duration-fast)}
details[open]>.summary .chev,details[open]>summary .chev,[aria-expanded="true"]>.chev{transform:rotate(180deg)}
.dropdown{position:absolute;top:calc(100% + 8px);left:0;z-index:60;min-width:176px;margin:0;padding:6px;list-style:none;display:flex;flex-direction:column;gap:2px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius-md);box-shadow:var(--shadow-inset),var(--shadow-pop)}
.dropdown a{display:flex;align-items:center;min-height:36px;padding:6px 12px;border-radius:var(--radius-sm);font-size:14px;color:var(--text);text-decoration:none}
.dropdown a:hover,.dropdown a[aria-current="true"]{background:var(--bg-panel-2)}
.lang .dropdown,.preview-menu .dropdown{left:auto;right:0}
.lang-button{font-size:14px;width:auto;min-width:44px}
.topbar-end{margin-left:auto;display:flex;align-items:center;gap:12px;flex-shrink:0}
.btn-login{display:inline-flex;align-items:center;justify-content:center;min-height:40px;padding:0 20px;border-radius:var(--radius-pill);background:var(--bg-panel);border:1px solid var(--border-strong);box-shadow:var(--shadow-inset),0 1px 2px var(--ink-06);color:var(--text);font-size:15px;font-weight:var(--weight-medium);text-decoration:none;white-space:nowrap}
.btn-login:hover{border-color:var(--text)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--radius-sm)}
.menu-icon{width:20px;height:20px;display:block}
.mobile-drawer{position:fixed;top:var(--header-height);right:0;left:0;z-index:52;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--bg-panel);padding:16px var(--gutter) 32px}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;color:var(--text);text-decoration:none;border-radius:var(--radius-sm)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current]{background:var(--bg-panel-2)}
.drawer-languages{padding-top:16px;margin-top:16px;border-top:1px solid var(--border)}
.nav-veil{position:fixed;inset:var(--header-height) 0 0;z-index:51;background:var(--scrim);border:0}
html.nav-open{overflow:hidden}
.preview-menu{display:none}
.site-footer{margin-top:var(--space-8);padding-top:var(--space-9);padding-bottom:var(--space-6);border-top:1px solid var(--border);background:var(--bg-panel-2)}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:var(--space-8)}
.footer-grid>*{min-width:0}
.footer-intro{margin-top:var(--space-5);max-width:34em;color:var(--text-muted)}
.footer-title{margin:0 0 var(--space-4);font-size:16px;font-weight:var(--weight-medium)}
.footer-links{list-style:none;margin:0;padding:0;display:grid;gap:6px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:28px;color:var(--text-muted);text-decoration:none}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent-dark);text-decoration:underline}
.footer-languages,.footer-legal{display:flex;flex-wrap:wrap;gap:8px 24px}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;gap:16px;margin-top:var(--space-8);padding-top:var(--space-5);border-top:1px solid var(--border-strong);font-size:14px;color:var(--text-muted)}
.footer-bottom p{margin:0}
.reveal{transition:opacity var(--duration-reveal) var(--ease-out),transform var(--duration-reveal) var(--ease-out)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-width:0;max-width:100%;min-height:120px;overflow:hidden;margin-top:var(--space-5);margin-bottom:var(--space-6)}
#server-status+*{margin-top:var(--space-6)}
#server-status>*{min-width:0;max-width:100%}
body:has(.toc-tabs) section[id]{scroll-margin-top:var(--toc-offset)}
.prose{min-width:0;overflow-wrap:break-word}
.prose h2{margin-top:var(--space-9)}
.prose h3{margin-top:var(--space-7)}
.prose p,.prose li{line-height:1.85}
.prose img{border-radius:var(--radius-sm)}
@media(min-width:961px){
  html.nav-open{overflow:auto}
  .mobile-drawer,.nav-veil{display:none!important}
}
@media(max-width:1280px){
  .topbar{gap:24px;padding-inline:32px}
  .mainnav a,.nav-more>summary{padding-inline:10px;font-size:14px}
}
@media(max-width:1120px){
  .brand-zh{display:none}
  .topbar{gap:20px}
}
@media(max-width:960px){
  .mainnav{display:none}
  .menu-toggle{display:inline-flex}
  .preview-menu{display:block}
  .topbar-end{margin-left:auto}
  .grid-five{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media(max-width:768px){
  :root{--header-height:64px;--anchor-offset:80px;--toc-offset:144px;--gutter:20px;--size-h2:32px;--size-h3:22px;--space-10:64px}
  h1{font-size:36px;line-height:1.18}
  .topbar{padding-inline:16px;gap:12px}
  .topbar-end{gap:8px;margin-left:auto}
  .lang{display:none}
  .grid-three,.grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
  .footer-grid>:first-child{grid-column:1/-1}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .tilt,.decorative-tilt{transform:none}
  .grid-three,.grid-five{grid-template-columns:minmax(0,1fr)}
  .brand-en{font-size:16px}
  .brand-mark{width:28px;height:28px}
  .btn-login{padding-inline:14px;font-size:14px}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .footer-grid>:first-child{grid-column:auto}
  .footer-bottom{flex-direction:column}
  .mobile-drawer{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-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
}