:root{
  --bg:#EAEDF7;--bg-panel:#F8F9FD;--bg-panel-2:#DDE2F0;--bg-side:#F4F6FB;--surface:#FFFFFF;
  --hero-top:#F3F5FB;--hero-bottom:#E3E8F4;--border:#CBD2E6;--border-soft:#DCE1EF;
  --accent:#E97A45;--accent-deep:#D96833;--accent-dark:#B9562A;--text:#232838;--text-muted:#5C6378;
  --success:#2F9A5B;--link:#5B6BD6;--warn:#C98A12;--error:#CF3B3B;
  --success-soft:rgba(47,154,91,.12);--link-soft:rgba(91,107,214,.12);--accent-soft:rgba(233,122,69,.08);
  --candy:color-mix(in srgb,var(--accent) 8%,var(--bg-panel));
  --doodle-faint:#B4BCD6;--hi-edge:rgba(255,255,255,.95);--hi-face:rgba(255,255,255,.8);
  --hi-clear:rgba(255,255,255,0);--glass:rgba(255,255,255,.62);--btn-highlight:rgba(255,255,255,.28);
  --topbar-line:rgba(35,40,56,.07);--veil:rgba(35,40,56,.28);
  --shadow-plate:0 44px 90px -34px rgba(233,122,69,.10),0 22px 48px -20px rgba(233,122,69,.10),0 2px 6px rgba(52,62,110,.06);
  --shadow-card:0 20px 44px -14px rgba(233,122,69,.14),0 6px 14px rgba(233,122,69,.08);
  --shadow-soft:0 12px 26px -12px rgba(52,62,110,.20),0 2px 4px rgba(52,62,110,.06);
  --shadow-btn:0 10px 22px -10px rgba(185,86,42,.55);--shadow-window:0 1px 2px rgba(52,62,110,.06);
  --flag-red:#D7263D;--flag-white:#FFFFFF;--flag-blue:#2E3B82;--flag-black:#1E1F25;--flag-gold:#F2C230;
  --r-focus:6px;--r-sm:8px;--r-md:12px;--r-lg:16px;--r-xl:24px;--r-candy:28px;--r-pill:999px;--r-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","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --fs-xs:12px;--fs-caption:12.5px;--fs-sm:14px;--fs-nav:14.5px;--fs-base:16px;--fs-button:16.5px;
  --fs-lede:20px;--fs-h3:24px;--fs-h2:36px;--fs-display:66px;
  --weight-normal:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-display:800;
  --gutter:24px;--wrap:1240px;--header-height:64px;--anchor-gap:80px;--toc-offset:12px;--chapter-offset:92px;
  --ease:ease;--fast:.18s;--reveal-duration:.35s;
}
*,*::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(--fs-base);line-height:1.6;-webkit-font-smoothing:antialiased}
[hidden]{display:none!important}
a{color:var(--link);text-decoration:none}
a:hover{text-decoration:underline;text-underline-offset:4px}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
p{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
h1,h2,h3,h4{font-family:var(--font-display);color:var(--text);text-wrap:balance}
h1{font-size:clamp(52px,4.6vw,68px);line-height:1.12;letter-spacing:-.02em;font-weight:var(--weight-display)}
h2{font-size:var(--fs-h2);line-height:1.25;letter-spacing:-.02em}
h3{font-size:var(--fs-h3);line-height:1.35}
:focus-visible{outline:2px solid var(--link);outline-offset:3px;border-radius:var(--r-focus)}
.no-break{white-space:nowrap}
.mono,code,pre{font-family:var(--font-mono)}
.mono{font-size:.94em;letter-spacing:-.01em}
code{overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--bg-panel-2);border-radius:var(--r-md)}
pre code{overflow-wrap:normal;white-space:pre}
.wrap{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:72px;padding-bottom:72px}
.section-heading{margin:0 0 28px}
.section-intro{max-width:760px;margin-bottom:28px;color:var(--text-muted);font-size:var(--fs-lede)}
.grid{display:grid;gap:24px}
.grid>*{min-width:0}
.grid--three{grid-template-columns:repeat(3,minmax(0,1fr))}
.panel,.card{min-width:0;background:var(--bg-panel);border:1px solid var(--border-soft);border-radius:var(--r-xl);box-shadow:inset 0 1px 0 var(--hi-edge),var(--shadow-plate);padding:28px}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-block:18px}
.prose ul{list-style:disc;padding-left:24px}
.prose ol{list-style:decimal;padding-left:24px}
.prose h2{margin-top:48px}
.prose h3{margin-top:32px}
.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}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:50px;padding:10px 30px;border:0;border-radius:var(--r-pill);font-size:var(--fs-button);font-weight:var(--weight-bold);letter-spacing:.01em;text-align:center;flex-shrink:0;white-space:nowrap;transition:transform var(--fast) var(--ease),box-shadow var(--fast) var(--ease),background var(--fast) var(--ease)}
.btn:hover{text-decoration:none}
.btn svg{width:18px;height:18px}
.btn--primary,.btn-primary{background:linear-gradient(180deg,var(--accent),var(--accent-deep));color:var(--surface);box-shadow:inset 0 1px 0 var(--btn-highlight),var(--shadow-btn)}
.btn--primary:hover,.btn-primary:hover{transform:translateY(-1px)}
.btn--ghost{border:1.5px solid var(--text);color:var(--text);background:var(--glass)}
.btn--ghost:hover{background:var(--surface)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.55;pointer-events:none;box-shadow:none}
.btn--small{min-height:40px;padding:8px 20px;font-size:var(--fs-sm)}
.cta-row{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin-bottom:18px}
.reveal{transition:opacity var(--reveal-duration) var(--ease),transform var(--reveal-duration) var(--ease)}
.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%;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:24px}
#server-status>*{min-width:0;max-width:100%}

/* Shared header */
#site-header{position:relative;z-index:50;min-height:var(--header-height)}
.topbar{background:var(--hero-top);border-bottom:1px solid var(--topbar-line);position:relative;z-index:50}
.topbar__inner{max-width:var(--wrap);margin:0 auto;height:var(--header-height);padding:0 var(--gutter);display:flex;align-items:center;gap:28px;flex-wrap:nowrap}
.brand{display:inline-flex;align-items:center;gap:10px;color:var(--text);flex-shrink:0}
.brand:hover{text-decoration:none}
.brand__mark{width:28px;height:28px;display:block}
.brand__word{font-family:var(--font-display);font-weight:var(--weight-display);font-size:var(--fs-lede);letter-spacing:-.03em;white-space:nowrap}
.tabs{flex:1;min-width:0;align-self:stretch;overflow-x:auto}
.tabs__list{display:flex;align-items:center;list-style:none;margin:0;padding:0;height:100%;gap:2px}
.tabs__list>li{height:100%;flex-shrink:0}
.tabs__link{position:relative;display:flex;align-items:center;height:100%;min-height:44px;padding:0 12px;font-size:var(--fs-nav);font-weight:var(--weight-medium);color:var(--text-muted);white-space:nowrap}
.tabs__link::after{content:"";position:absolute;left:12px;right:12px;bottom:0;height:2px;border-radius:var(--r-sm);background:var(--text);transform:scaleX(0)}
.tabs__link:hover{color:var(--text);text-decoration:none}
.tabs__link.is-current{color:var(--text);font-weight:var(--weight-semibold)}
.tabs__link.is-current::after{transform:scaleX(1)}
.topbar__end{display:flex;align-items:center;gap:10px;flex-shrink:0;margin-left:auto}
.language{position:relative}
.lang-switch{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;height:36px;padding:0 12px;border:0;border-radius:var(--r-pill);background:var(--hi-clear);color:var(--text-muted);font-size:var(--fs-sm);white-space:nowrap}
.lang-switch:hover{background:var(--bg-panel-2);color:var(--text)}
.lang-switch svg{width:16px;height:16px}
.lang-text{white-space:nowrap}
.lang-panel{position:absolute;right:0;top:calc(100% + 10px);z-index:80;min-width:180px;padding:8px;background:var(--surface);border:1px solid var(--border);border-radius:var(--r-lg);box-shadow:var(--shadow-soft)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;color:var(--text);border-radius:var(--r-sm)}
.lang-panel a:hover,.lang-panel a[aria-current]{background:var(--bg-panel-2);text-decoration:none}
.btn-login{display:inline-flex;align-items:center;justify-content:center;min-height:38px;padding:7px 20px;border-radius:var(--r-pill);background:var(--text);color:var(--bg-panel);font-size:var(--fs-nav);font-weight:var(--weight-semibold);white-space:nowrap}
.btn-login:hover{background:var(--text-muted);text-decoration:none}
.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(--bg-panel);color:var(--text)}
.menu-toggle svg{width:20px;height:20px;fill:none;stroke:currentColor;stroke-width:2;stroke-linecap:round}
.menu-drawer{display:none}
.menu-veil{display:none}
html.nav-open{overflow:hidden}

/* Shared footer */
.site-footer{background:var(--bg-panel-2);border-top:1px solid var(--hi-edge);padding-top:48px;padding-bottom:28px}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-about{color:var(--text-muted);margin-top:16px;max-width:380px}
.footer-title{font-size:var(--fs-base);margin:0 0 12px;font-weight:var(--weight-bold)}
.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:28px;color:var(--text-muted);font-size:var(--fs-sm)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:28px;padding-top:20px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;flex-wrap:wrap;justify-content:space-between;gap:12px;margin-top:20px;font-size:var(--fs-sm);color:var(--text-muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:20px}
@media(max-width:1100px){
  .topbar__inner{gap:16px}
  .tabs__link{padding-inline:9px}
}
@media(max-width:1040px){
  .tabs{display:none}
  .topbar__end{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .menu-drawer{display:block;position:fixed;inset-inline:0;top:var(--header-height);height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;z-index:48;background:var(--bg-panel);padding:16px var(--gutter) 32px}
  .menu-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;color:var(--text);border-radius:var(--r-sm)}
  .menu-drawer a:hover,.menu-drawer a[aria-current]{background:var(--bg-panel-2);text-decoration:none}
  .menu-languages{border-top:1px solid var(--border);margin-top:16px;padding-top:12px}
  .menu-veil{display:block;position:fixed;inset:var(--header-height) 0 0;z-index:47;background:var(--veil);border:0}
}
@media(max-width:768px){
  :root{--fs-h2:28px;--gutter:16px}
  h1{font-size:40px}
  .grid--three{grid-template-columns:1fr}
  .section{padding-top:48px;padding-bottom:48px}
  .footer-grid{grid-template-columns:1fr;gap:28px}
  .panel,.card{padding:22px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  h1{font-size:36px}
  .tilt,.sticker{transform:none}
  .topbar__inner{gap:10px}
  .brand__word{font-size:18px}
  .lang-switch .lang-text{display:none}
  .lang-switch{padding-inline:8px}
  .topbar__end{gap:6px;margin-left:auto}
  .btn-login{padding-inline:14px}
  .hero__texture,.doodle{max-width:100%}
}
@media(max-width:360px){
  .brand{gap:6px}
  .brand__mark{width:24px;height:24px}
  .brand__word{font-size:var(--fs-base)}
  .topbar__inner{gap:6px}
  .btn-login{padding-inline:11px}
  .topbar__end{gap:4px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition:none!important;animation:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}