:root{
  color-scheme:light;
  --bg:#E9ECF8;
  --bg-top:#F1F3FB;
  --bg-bottom:#E2E6F5;
  --panel:#F7F8FE;
  --panel-white:#FFFFFF;
  --panel-2:#DDE2F3;
  --land-hi:#DDE2F3;
  --land-lo:#CFD7EE;
  --ocean:#EEF1FA;
  --border:#C9D0E8;
  --border-soft:#DCE1F0;
  --accent:#1F6E8C;
  --accent-2:#3A8FB0;
  --accent-dark:#164F66;
  --accent-tint:#E2EEF4;
  --accent-tint-2:#CFE3EC;
  --text:#18213A;
  --text-muted:#56607E;
  --text-faint:#8C94AF;
  --success:#1E8A5A;
  --warn:#B7791F;
  --error:#C2413A;
  --white:#FFFFFF;
  --dot-1:#C9D0E8;
  --dot-2:#D3D9EC;
  --dot-3:#DDE2F3;
  --flag-red:#C9413F;
  --flag-blue:#2D4A7E;
  --flag-green:#3A8B5D;
  --flag-white:#FFFFFF;
  --flag-edge:rgba(24,33,58,.14);
  --glass-hi:rgba(255,255,255,.95);
  --on-dark-hi:rgba(255,255,255,.3);
  --on-dark-soft:rgba(255,255,255,.14);
  --on-dark-line:rgba(255,255,255,.18);
  --on-dark-muted:rgba(255,255,255,.76);
  --ink-05:rgba(24,33,58,.05);
  --ink-06:rgba(24,33,58,.06);
  --grid-line:rgba(31,110,140,.04);
  --steel-08:rgba(31,110,140,.08);
  --steel-12:rgba(31,110,140,.12);
  --steel-14:rgba(31,110,140,.14);
  --steel-18:rgba(31,110,140,.18);
  --steel-22:rgba(31,110,140,.22);
  --steel-30:rgba(31,110,140,.30);
  --glow:rgba(31,110,140,.16);
  --veil:rgba(24,33,58,.32);
  --clear:transparent;
  --shadow-near:0 2px 6px var(--ink-06);
  --shadow-far:0 28px 64px var(--steel-14);
  --shadow-far-strong:0 32px 72px var(--steel-22);
  --shadow-float:0 14px 32px var(--steel-18);
  --shadow-nav:0 14px 36px var(--steel-08);
  --shadow-cta:0 12px 28px var(--steel-30);
  --shadow-card:0 12px 32px var(--steel-12);
  --hl:inset 0 1px 0 var(--glass-hi);
  --radius-xs:4px;
  --radius-s:6px;
  --radius:8px;
  --radius-m:12px;
  --radius-phone:26px;
  --radius-screen:20px;
  --radius-pill:999px;
  --radius-round:50%;
  --font-display:'Inter','Noto Sans SC','PingFang SC','Hiragino Sans','Microsoft YaHei','Malgun Gothic',sans-serif;
  --font-body:'Inter','Noto Sans SC','PingFang SC','Hiragino Sans','Microsoft YaHei','Malgun Gothic',system-ui,sans-serif;
  --font-mono:'JetBrains Mono',ui-monospace,'SFMono-Regular',Menlo,Consolas,monospace;
  --gutter:24px;
  --wrap-width:1200px;
  --anchor-offset:96px;
  --toc-offset:16px;
  --toc-landing:104px;
  --ease:cubic-bezier(.2,.65,.3,1);
  --duration-fast:.2s;
  --duration-reveal:.6s;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
body{
  margin:0;min-width:320px;font-family:var(--font-body);font-size:16px;line-height:1.75;color:var(--text);
  background-color:var(--bg);
  background-image:linear-gradient(var(--grid-line) 1px,var(--clear) 1px),linear-gradient(90deg,var(--grid-line) 1px,var(--clear) 1px),linear-gradient(180deg,var(--bg-top) 0,var(--bg-bottom) 900px,var(--bg) 1120px);
  background-size:40px 40px,40px 40px,100% 100%;background-position:center top,center top,0 0;
  -webkit-font-smoothing:antialiased;
}
html.nav-open{overflow:hidden}
[hidden]{display:none!important}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button,select,input,textarea{border:1px solid var(--border);border-radius:var(--radius-s)}
button{background:var(--panel)}
button:disabled,.btn[aria-disabled="true"]{cursor:not-allowed;opacity:.55;transform:none;box-shadow:none}
input,select,textarea{max-width:100%;padding:10px 12px;background:var(--panel-white)}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
:where(a,button,input,select,textarea,summary,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:3px}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:800;line-height:1.3;text-wrap:balance;overflow-wrap:break-word}
h1{font-size:clamp(52px,5vw,66px);line-height:1.1;letter-spacing:-.02em}
h2{font-size:clamp(28px,3vw,40px);color:var(--accent-dark)}
h3{font-size:21px}
p{margin:0 0 1em}
h1,h2,h3{margin-top:0}
ul,ol{padding-inline-start:1.5em}
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(--radius);line-height:1.7}
pre code{overflow-wrap:normal;white-space:pre}
blockquote{margin-inline:0}
table{border-collapse:collapse}
th{text-align:start}
hr{border:0;border-top:1px solid var(--border);margin-block:32px}
.wrap{width:100%;max-width:var(--wrap-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:80px;padding-bottom:80px}
.section-heading{max-width:760px;margin-bottom:32px}
.section-heading p{color:var(--text-muted)}
.prose{max-width:820px;overflow-wrap:break-word}
.prose h2{margin-top:2em;font-size:30px}
.prose h3{margin-top:1.5em}
.prose a:not(.btn){color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
.prose li+li{margin-top:8px}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid>*{min-width:0}
.panel,.card{min-width:0;padding:24px;background:var(--panel);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--hl),var(--shadow-card)}
.card{transition:transform var(--duration-fast),box-shadow var(--duration-fast)}
.card:hover{transform:translateY(-2px);box-shadow:var(--hl),var(--shadow-float)}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.no-break{white-space:nowrap}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.ico{display:block;width:18px;height:18px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round;flex:none}
.eyebrow{margin:0;font-family:var(--font-display);font-size:13px;line-height:18px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--text-muted)}
.icon-plate{display:grid;place-items:center;width:44px;height:44px;background:var(--accent-tint);color:var(--accent);border-radius:var(--radius-s);flex:none}
.icon-plate svg{width:24px;height:24px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:50px;padding:10px 30px;border:1px solid var(--clear);border-radius:var(--radius-pill);font-size:16px;font-weight:600;letter-spacing:.01em;line-height:1.5;white-space:nowrap;flex-shrink:0;transition:transform var(--duration-fast),box-shadow var(--duration-fast),background-color var(--duration-fast)}
.btn:hover{transform:translateY(-1px)}
.btn-primary{color:var(--white);background:linear-gradient(135deg,var(--accent-2) 0%,var(--accent) 58%,var(--accent-dark) 100%);box-shadow:inset 0 1px 0 var(--on-dark-hi),var(--shadow-near),var(--shadow-cta)}
.btn-ghost,.btn-secondary{color:var(--accent-dark);background:var(--panel-white);border:1.5px solid var(--accent);box-shadow:var(--hl),var(--shadow-near)}
.btn-primary:active,.btn-ghost:active,.btn-secondary:active{transform:translateY(0);box-shadow:var(--shadow-near)}
.btn-small{min-height:40px;padding:8px 18px;font-size:14px}
.cta-row{display:flex;justify-content:center;flex-wrap:wrap;gap:14px;margin-top:24px}
.announce{background:var(--accent-dark);color:var(--white);font-size:13.5px;line-height:20px;padding:8px 16px;text-align:center;letter-spacing:.01em}
.announce .sep{opacity:.6;margin:0 8px}
.announce a{display:inline-block;min-height:24px;margin-left:12px;font-weight:600;white-space:nowrap;text-decoration:underline;text-decoration-color:var(--white);text-decoration-thickness:1px;text-underline-offset:3px}
.topnav{position:relative;z-index:30;padding:10px 24px 0}
.navbar{position:relative;max-width:1320px;margin:0 auto;min-height:56px;display:flex;align-items:center;gap:8px;padding:8px 10px 8px 16px;background:var(--panel-white);border:1px solid var(--border-soft);border-radius:var(--radius-m);box-shadow:var(--hl),var(--shadow-near),var(--shadow-nav)}
.brand{display:flex;align-items:center;gap:10px;flex:none;min-height:38px}
.brand-mark{width:32px;height:32px;border-radius:var(--radius);flex:none}
.brand-name{font-family:var(--font-display);font-weight:800;font-size:19px;letter-spacing:-.01em;color:var(--accent-dark)}
.nav-links{margin-inline:auto}
.nav-links ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px}
.nav-links a{display:flex;align-items:center;gap:6px;min-height:38px;padding:0 10px;border-radius:var(--radius);font-size:14px;font-weight:500;color:var(--text);white-space:nowrap;transition:background-color var(--duration-fast)}
.nav-links a .ico{color:var(--accent);width:16px;height:16px}
.nav-links a:hover,.nav-links a[aria-current="page"]{background:var(--accent-tint);color:var(--accent-dark)}
.nav-links a[aria-current="page"]{font-weight:600}
.nav-end{display:flex;align-items:center;gap:6px;flex:none}
.language-control{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;min-height:38px;padding:0 10px;border:0;border-radius:var(--radius);background:var(--clear);font-size:13.5px;color:var(--text-muted);white-space:nowrap}
.lang-caption{white-space:nowrap}
.lang:hover{background:var(--accent-tint)}
.language-menu{position:absolute;top:calc(100% + 10px);right:0;min-width:180px;padding:6px;background:var(--panel-white);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-float)}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--radius-s)}
.language-menu a:hover,.language-menu a[aria-current="true"]{background:var(--accent-tint);color:var(--accent-dark)}
.login{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:38px;padding:0 18px 0 14px;border-radius:var(--radius-pill);background:var(--accent);color:var(--white);font-size:14px;font-weight:600;white-space:nowrap;box-shadow:inset 0 1px 0 var(--on-dark-hi),0 6px 14px var(--steel-22);transition:background-color var(--duration-fast)}
.login:hover{background:var(--accent-dark)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:8px;border:0;background:var(--accent-tint);color:var(--accent-dark)}
.nav-drawer{display:none}
.nav-veil{position:fixed;inset:0;background:var(--veil);z-index:29;border:0;border-radius:0}
.site-footer{margin-top:48px;padding-top:56px;padding-bottom:24px;background:var(--panel-2);border-top:1px solid var(--border);box-shadow:var(--hl)}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-brand p{margin-top:16px;max-width:360px;color:var(--text-muted);font-size:14px}
.footer-title{margin:0 0 12px;font-size:15px;font-weight:700;color:var(--accent-dark)}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 16px}
.footer-links a,.footer-languages a,.legal-links a{display:inline-flex;align-items:center;min-height:28px;font-size:14px}
.footer-links a:hover,.footer-languages a:hover,.legal-links a:hover{color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:32px;padding-top:20px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:12px;margin-top:16px;color:var(--text-muted);font-size:13px}
.legal-links{display:flex;flex-wrap:wrap;gap:16px}
.reveal{transition:opacity var(--duration-reveal) var(--ease),transform var(--duration-reveal) 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%;min-height:120px;overflow:hidden;margin-block:24px}
#server-status+*{margin-top:32px}
.decorated-section{position:relative;overflow-x:clip}
@media(max-width:1200px){
  .nav-links{display:none}
  .nav-end{margin-left:auto}
  .menu-toggle{display:inline-flex}
  .nav-drawer:not([hidden]){display:block;position:absolute;top:calc(100% + 10px);left:0;right:0;z-index:32;max-height:calc(100dvh - 160px);overflow-y:auto;overscroll-behavior:contain;padding:12px;background:var(--panel-white);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow-float)}
  .nav-drawer a{display:flex;align-items:center;gap:10px;width:100%;min-height:44px;padding:10px 14px;border-radius:var(--radius-s)}
  .nav-drawer a:hover,.nav-drawer a[aria-current]{background:var(--accent-tint);color:var(--accent-dark)}
  .drawer-languages{border-top:1px solid var(--border);margin-top:12px;padding-top:12px}
}
@media(max-width:900px){
  .grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-grid{grid-template-columns:1fr 1fr}
  .footer-brand{grid-column:1/-1}
}
@media(max-width:768px){
  h1{font-size:clamp(28px,6.3vw,40px);line-height:1.15}
  .section{padding-top:48px;padding-bottom:48px}
  .section-heading{margin-bottom:24px}
}
@media(max-width:640px){
  :root{--gutter:16px;--toc-landing:96px}
  .no-break{white-space:normal}
  .topnav{padding:8px 12px 0}
  .navbar{padding:6px 6px 6px 10px;gap:4px}
  .brand{gap:6px}
  .brand-name{font-size:17px}
  .brand-mark{width:28px;height:28px}
  .nav-end{margin-left:auto;gap:3px}
  .lang{padding-inline:8px;min-height:44px}
  .lang-caption{display:none}
  .login{min-height:40px;padding-inline:12px}
  .login .ico{display:none}
  .announce{font-size:12px}
  .announce .sep{margin-inline:4px}
  .announce a{margin-left:6px}
  .grid,.footer-grid{grid-template-columns:minmax(0,1fr)}
  .panel,.card{padding:20px}
  .tilt{transform:none}
  .decorated-section{max-width:100%}
  .footer-grid{gap:28px}
  .footer-brand{grid-column:auto}
  .btn{padding-inline:24px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none}
}