:root{
  --bg:#E7EDF5;--bg-top:#EEF3F9;--bg-bottom:#E1E9F3;
  --panel:#F7F9FD;--panel-2:#D9E2EE;--white:#FFFFFF;--selected:#EEF3F9;
  --border:#C9D4E3;--accent:#EA5B30;--accent-dark:#BF3F17;--amber:#F49A3C;
  --text:#1E2633;--muted:#5A6577;--faint:#7F8A9C;
  --success:#1F9D6B;--success-deep:#137A51;--warn:#C98A0B;--error:#D23A4A;
  --sketch:#9FB2CB;--sketch-fill:#E3E9F2;
  --side:#1E2633;--side-raise:#2F3A4C;--side-text:#BCC7D6;--side-cap:#7D8AA0;
  --warm-1:#FFFDF8;--warm-2:#EFE7DB;
  --flag-red:#D7333D;--flag-blue:#2E4C8A;--flag-white:#FFFFFF;
  --flag-edge:rgba(30,38,51,.16);--shadow-accent:rgba(234,91,48,.10);
  --shadow-cool:rgba(48,82,132,.12);--shadow-soft:rgba(48,82,132,.08);
  --glow:rgba(234,91,48,.06);--hi-line:rgba(255,255,255,.92);
  --win-edge:rgba(30,38,51,.08);--sheen:rgba(255,255,255,.07);
  --success-ring:rgba(31,157,107,.18);--switch-inset:rgba(8,44,28,.38);
  --knob-shadow:rgba(10,52,34,.34);--btn-shadow:rgba(191,63,23,.26);
  --btn-glint:rgba(255,255,255,.22);--veil:rgba(30,38,51,.34);
  --clear:transparent;--mask-solid:#000000;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei","Apple SD Gothic Neo","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-card:10px;--r-btn:8px;--r-win:14px;--r-pill:999px;--r-dot:50%;--r-small:4px;
  --gutter:24px;--page-width:1248px;--head-height:68px;
  --anchor-offset:84px;--toc-offset:16px;--chapter-offset:96px;
  --size-body:16px;--size-small:14px;--size-h1:64px;--size-h2:36px;--size-h3:22px;
  --weight-normal:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-display:800;
  --ease: cubic-bezier(.2,.7,.2,1);--speed:.2s;
  --panel-shadow:0 24px 60px -32px var(--shadow-accent),0 18px 36px -24px var(--shadow-cool);
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
html.nav-open{overflow:hidden}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--size-body);line-height:1.6;-webkit-font-smoothing:antialiased}
[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,svg{vertical-align:middle;max-width:100%}
img{height:auto}
svg{flex-shrink:0}
p,ul,ol,blockquote,figure{margin:0}
ul,ol{padding-left:1.5em}
h1,h2,h3,h4{font-family:var(--font-display);color:var(--text);text-wrap:balance}
h1,.h1{margin:0 0 16px;font-weight:var(--weight-display);font-size:clamp(52px,4.45vw,68px);line-height:1.1;letter-spacing:-.02em}
h2{margin:0 0 24px;font-size:var(--size-h2);line-height:1.25;letter-spacing:-.02em;font-weight:var(--weight-display)}
h3{margin:0 0 12px;font-size:var(--size-h3);line-height:1.4;font-weight:var(--weight-bold)}
h4{margin:0 0 8px}
.no-break{white-space:nowrap}
.wrap{width:100%;max-width:var(--page-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:80px;padding-bottom:80px}
.section-head{max-width:760px;margin:0 auto 40px;text-align:center}
.section-head p{color:var(--muted)}
.stack{display:grid;gap:24px}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid>* , .stack>*{min-width:0}
.panel,.card{min-width:0;padding:24px;border:1px solid var(--border);border-radius:var(--r-card);background:var(--panel);box-shadow:var(--panel-shadow)}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.text-link,.prose a:not(.btn){color:var(--accent-dark);text-decoration:underline;text-underline-offset:4px}
.text-link{display:inline-block;min-height:24px}
.prose{max-width:820px;margin-inline:auto;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-bottom:24px}
.prose h2{margin-top:56px}
.prose h3{margin-top:32px}
.prose li+li{margin-top:8px}
code{font-family:var(--font-mono);font-size:.9em;overflow-wrap:anywhere;background:var(--panel-2);border-radius:var(--r-small);padding:2px 5px}
pre{max-width:100%;overflow-x:auto;padding:20px;border:1px solid var(--border);border-radius:var(--r-card);background:var(--panel);-webkit-overflow-scrolling:touch}
pre code{white-space:pre;overflow-wrap:normal;background:var(--clear);padding:0}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent-dark);outline-offset:3px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:46px;padding:10px 24px;border:1px solid var(--clear);border-radius:var(--r-btn);font-size:var(--size-body);font-weight:var(--weight-semibold);line-height:24px;white-space:nowrap;flex-shrink:0;transition:transform var(--speed),box-shadow var(--speed),border-color var(--speed)}
.btn svg{width:16px;height:16px}
.btn-main,.btn-primary{min-width:156px;color:var(--white);background:linear-gradient(105deg,var(--accent-dark) 0%,var(--accent) 48%,var(--amber) 130%);box-shadow:0 12px 26px -12px var(--btn-shadow),inset 0 1px 0 var(--btn-glint)}
.btn-main:hover,.btn-primary:hover,.btn-main.is-hover{transform:translateY(-1px);box-shadow:0 16px 30px -12px var(--btn-shadow),inset 0 1px 0 var(--btn-glint)}
.btn-ghost,.btn-secondary{min-width:132px;color:var(--text);background:var(--panel);border-color:var(--border);box-shadow:0 6px 16px -12px var(--shadow-cool)}
.btn-ghost:hover,.btn-secondary:hover{transform:translateY(-1px);border-color:var(--sketch)}
.btn:active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);color:var(--muted);box-shadow:none;border-color:var(--border);transform:none}
.btn.is-focus{outline:2px solid var(--accent-dark);outline-offset:3px}
.cta-row{display:flex;flex-wrap:wrap;justify-content:center;gap:12px;margin-bottom:16px}
.site-head,#site-header{position:relative;z-index:50}
.head-row{position:relative;height:var(--head-height);display:flex;align-items:center;gap:20px}
.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0;min-height:36px}
.brand-mark{width:30px;height:30px;flex-shrink:0}
.brand-word{font-family:var(--font-display);font-weight:var(--weight-display);font-size:19px;letter-spacing:-.02em;color:var(--text)}
.nav{margin-left:auto}
.nav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px}
.nav a{display:block;padding:6px 12px;border-radius:var(--r-pill);font-size:14.5px;color:var(--muted);transition:color var(--speed),background-color var(--speed)}
.nav a:hover{color:var(--text)}
.nav a[aria-current="page"]{background:var(--panel-2);color:var(--text);font-weight:var(--weight-semibold)}
.head-tools{display:flex;align-items:center;gap:10px;flex-shrink:0}
.language-picker{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;width:auto;padding:6px 10px;font-size:var(--size-small);color:var(--muted);border:0;background:var(--clear);border-radius:var(--r-btn);white-space:nowrap}
.lang svg{width:16px;height:16px}
.lang span{white-space:nowrap}
.language-menu{position:absolute;top:calc(100% + 8px);right:0;min-width:170px;padding:8px;border:1px solid var(--border);border-radius:var(--r-card);background:var(--panel);box-shadow:var(--panel-shadow)}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-btn)}
.language-menu a:hover,.language-menu a[aria-current]{background:var(--panel-2)}
.login{display:inline-flex;align-items:center;justify-content:center;min-height:36px;padding:0 18px;border-radius:var(--r-btn);background:var(--text);color:var(--panel);font-size:var(--size-small);font-weight:var(--weight-semibold);white-space:nowrap;box-shadow:0 6px 16px -8px var(--shadow-cool)}
.login:hover{background:var(--side-raise)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;border:1px solid var(--border);border-radius:var(--r-btn);background:var(--panel)}
.menu-toggle svg{width:20px;height:20px}
.mobile-drawer{position:absolute;top:var(--head-height);left:var(--gutter);right:var(--gutter);z-index:52;padding:12px;border:1px solid var(--border);border-radius:var(--r-card);background:var(--panel);box-shadow:var(--panel-shadow);max-height:calc(100dvh - var(--head-height) - 16px);overflow-y:auto;overscroll-behavior:contain}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:10px 14px;border-radius:var(--r-btn);color:var(--text)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current]{background:var(--panel-2)}
.drawer-languages{border-top:1px solid var(--border);margin-top:8px;padding-top:8px}
.nav-veil{position:fixed;inset:var(--head-height) 0 0;z-index:40;background:var(--veil);border:0;width:100%}
.site-footer{border-top:1px solid var(--border);background:var(--bg-bottom);padding-top:56px;padding-bottom:28px}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:48px}
.footer-grid>*{min-width:0}
.footer-brand p{max-width:340px;margin-top:16px;color:var(--muted);font-size:var(--size-small)}
.footer-title{font-size:var(--size-body);font-weight:var(--weight-bold);margin-bottom:12px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 12px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px;font-size:var(--size-small);color:var(--muted);overflow-wrap:anywhere}
.footer-links a:hover,.footer-legal a:hover{color:var(--accent-dark)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;padding-top:32px}
.footer-languages a[aria-current]{color:var(--text);font-weight:var(--weight-semibold)}
.footer-bottom{display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;margin-top:24px;padding-top:20px;border-top:1px solid var(--border);font-size:var(--size-small);color:var(--muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:20px}
.reveal{transition:opacity .65s var(--ease),transform .65s 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%;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:24px}
.decor-zone{position:relative;overflow-x:clip;max-width:100%}
.ico{fill:none;stroke:currentColor;stroke-width:1.6;stroke-linecap:round;stroke-linejoin:round}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
@media(min-width:1041px){.mobile-drawer,.nav-veil{display:none!important}}
@media(max-width:1180px){.head-row{gap:12px}.nav a{padding-inline:9px}}
@media(max-width:1040px){.nav{display:none}.head-tools{margin-left:auto}.menu-toggle{display:inline-flex}}
@media(max-width:768px){
  h1,.h1{font-size:clamp(28px,9vw,40px)}
  h2{font-size:28px}
  .grid{grid-template-columns:1fr}
  .section{padding-top:48px;padding-bottom:48px}
  .footer-grid{grid-template-columns:1fr;gap:28px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .head-row{gap:8px}
  .head-tools{gap:6px;margin-left:auto}
  .brand{gap:6px}
  .brand-word{font-size:17px}
  .brand-mark{width:26px;height:26px}
  .login{padding-inline:12px}
  .lang{padding-inline:5px}
  .head-tools .lang span{display:none}
  .head-tools .lang{min-width:32px}
  .panel,.card{padding:20px}
  .tilt,.decor-tilt,[data-tilt]{transform:none}
  .decor-zone{max-width:100%}
  .btn{min-height:44px;padding-inline: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}
}