:root{
  --bg:#E1EFEE;--bg-top:#ECF6F5;--bg-bottom:#D8E9E8;--panel:#F6FAFA;--panel-2:#D3E5E4;--border:#C3D8D8;
  --accent:#16171B;--accent-dark:#07080A;--ink-face:#2A2C33;--text:#13191B;--text-soft:#34464A;--muted:#55686B;
  --success:#1E8A5C;--warn:#B4781E;--error:#C0413B;--white:#FFFFFF;--ice:#9ED9D6;
  --clear:transparent;--line-soft:rgba(22,23,27,.07);--ink-40:rgba(22,23,27,.4);--veil:rgba(22,23,27,.18);
  --glass:rgba(246,250,250,.62);--glass-strong:rgba(246,250,250,.84);--glass-edge:rgba(255,255,255,.92);--track:rgba(255,255,255,.88);
  --halo-0:rgba(255,255,255,.85);--halo-1:rgba(255,255,255,.52);--halo-2:rgba(255,255,255,.3);--halo-x:rgba(255,255,255,0);
  --tile-hi:rgba(255,255,255,.95);--tile-mid:rgba(226,244,242,.9);--tile-lo:rgba(158,217,214,.94);
  --sheen:rgba(255,255,255,.8);--sheen-band:rgba(255,255,255,.5);--sheen-x:rgba(255,255,255,0);
  --arrow-shadow:rgba(7,8,10,.22);--ring-flag:rgba(22,23,27,.16);
  --shadow-tile:0 36px 64px rgba(22,23,27,.12),0 8px 18px rgba(22,23,27,.05);
  --shadow-tile-inset:inset 0 0 0 1px rgba(255,255,255,.95),inset 0 2px 0 rgba(255,255,255,1),inset 0 -16px 30px rgba(22,23,27,.05);
  --shadow-float:0 16px 36px rgba(22,23,27,.10),0 2px 6px rgba(22,23,27,.05);
  --shadow-chip:0 6px 16px rgba(22,23,27,.07);--shadow-btn:0 12px 26px rgba(22,23,27,.16);
  --shadow-btn-sm:0 8px 18px rgba(22,23,27,.14);
  --inset-hi:inset 0 0 0 1px rgba(255,255,255,.9),inset 0 1px 0 rgba(255,255,255,1);
  --flag-white:#FFFFFF;--flag-us-red:#B22234;--flag-us-blue:#3C3B6E;--flag-sg-red:#EF3340;--flag-jp-red:#BC002D;--flag-hk-red:#DE2910;--flag-uk-blue:#012169;--flag-uk-red:#C8102E;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Yu Gothic","Apple SD Gothic Neo","Malgun Gothic","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Yu Gothic","Apple SD Gothic Neo","Malgun Gothic","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SF Mono",Menlo,Consolas,monospace;
  --fs-display:68px;--fs-section:56px;--fs-h2:36px;--fs-h3:22px;--fs-body:16px;--fs-lead:17px;--fs-small:14px;--fs-micro:12px;
  --weight-regular:400;--weight-medium:500;--weight-semibold:600;
  --r-pill:999px;--r-tile:48px;--r-card:10px;--r-small:3px;--r-line:2px;--r-round:50%;
  --max:1440px;--reading:800px;--pad-x:48px;--gutter:var(--pad-x);--u:1;--head-height:64px;--anchor-offset:80px;--toc-offset:88px;
  --ease:ease;--fast:.2s;--reveal-time:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-offset)}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--fs-body);font-weight:var(--weight-regular);line-height:1.6;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
img,svg{vertical-align:middle}
img{max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button,a,input,select,textarea,summary{-webkit-tap-highlight-color:var(--clear)}
button{border:0}
button:disabled,[aria-disabled="true"]{cursor:not-allowed}
[hidden]{display:none!important}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
p,h1,h2,h3,h4,figure,blockquote{margin:0}
ul{margin:0;padding:0;list-style:none}
h1,h2,h3{font-family:var(--font-display);font-weight:var(--weight-regular);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:var(--fs-display);line-height:1.12;letter-spacing:-.02em}
h2{font-size:var(--fs-h2);line-height:1.25;letter-spacing:-.02em}
h3{font-size:var(--fs-h3);line-height:1.4}
strong{font-weight:var(--weight-semibold)}
code,kbd,pre{font-family:var(--font-mono)}
code{overflow-wrap:anywhere;font-size:.9em}
pre{max-width:100%;overflow-x:auto;padding:20px;border-radius:var(--r-card);background:var(--panel-2)}
pre code{overflow-wrap:normal;white-space:pre}
input,textarea,select{max-width:100%;border:1px solid var(--border);border-radius:var(--r-card);background:var(--panel);padding:12px}
input:focus,textarea:focus,select:focus{border-color:var(--accent)}
section[id]{scroll-margin-top:var(--anchor-offset)}
.grid>*{min-width:0}
.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}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.no-break{white-space:nowrap}
.wrap{width:100%;max-width:var(--max);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.reading-wrap{width:100%;max-width:calc(var(--reading) + var(--gutter)*2);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.sec{padding-top:96px;padding-bottom:96px}
.stack{display:grid;gap:24px;min-width:0}
.grid{display:grid;gap:24px;min-width:0}
.grid-three{grid-template-columns:repeat(3,minmax(0,1fr))}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono)}
.panel,.card{min-width:0;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-card);box-shadow:var(--inset-hi)}
.card{padding:28px}
.panel-sunken{background:var(--panel-2)}
.section-heading{margin-bottom:40px;max-width:24em}
.section-heading p{margin-top:20px;color:var(--muted)}
.prose{min-width:0;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-bottom:24px}
.prose ul{padding-left:1.3em;list-style:disc}
.prose ol{padding-left:1.5em}
.prose h2{margin-top:56px;margin-bottom:24px}
.prose h3{margin-top:32px;margin-bottom:16px}
.prose a{text-decoration:underline;text-underline-offset:4px}
.prose li+li{margin-top:8px}
.prose img{border-radius:var(--r-card)}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:0 26px;border:1px solid var(--clear);border-radius:var(--r-pill);font-size:var(--fs-body);font-weight:var(--weight-medium);white-space:nowrap;flex-shrink:0;gap:8px;transition:transform var(--fast) var(--ease),background-color var(--fast) var(--ease),border-color var(--fast) var(--ease)}
.btn svg{width:18px;height:18px;flex-shrink:0}
.btn:hover{transform:translateY(-1px)}
.btn-primary{background:var(--accent);color:var(--panel);box-shadow:var(--shadow-btn)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--accent-dark)}
.btn-ghost,.btn-secondary{background:var(--panel);color:var(--text);border-color:var(--border);box-shadow:var(--shadow-chip)}
.btn-ghost:hover,.btn-secondary:hover,.btn-ghost.is-hover{border-color:var(--muted)}
.btn:active{transform:translateY(0)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.5;transform:none;box-shadow:none;pointer-events:none}
.btn.is-focus{outline:2px solid var(--accent);outline-offset:3px}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin-bottom:40px}
.badge,.chip,.tag{display:inline-flex;align-items:center;gap:8px;max-width:100%;min-height:28px;padding:3px 12px;border-radius:var(--r-pill);border:1px solid var(--border);background:var(--panel);color:var(--text-soft);font-size:var(--fs-micro);overflow-wrap:anywhere}
.badge-dot{width:6px;height:6px;border-radius:var(--r-round);background:var(--accent);flex-shrink:0}
.badge-ink{background:var(--accent);border-color:var(--accent);color:var(--panel)}
.reveal{transition:opacity var(--reveal-time) var(--ease),transform var(--reveal-time) 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:32px}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:32px}

/* Shared navigation */
.site-head{position:relative;z-index:50;border-bottom:1px solid var(--line-soft)}
.head-in{max-width:var(--max);margin:0 auto;height:var(--head-height);padding:0 var(--pad-x);display:flex;align-items:center;gap:36px;flex-wrap:nowrap;position:relative;z-index:53}
.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0;font-family:var(--font-display);font-size:17px;font-weight:var(--weight-semibold);letter-spacing:-.015em;color:var(--accent)}
.brand-mark{width:28px;height:28px;display:block;flex-shrink:0}
.tabs{flex:1;min-width:0;align-self:stretch;display:flex}
.tabs ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px;overflow-x:auto;scrollbar-width:none}
.tabs ul::-webkit-scrollbar{display:none}
.tab{position:relative;display:flex;align-items:center;justify-content:center;height:var(--head-height);padding:0 12px;font-size:14.5px;color:var(--muted);white-space:nowrap;transition:color var(--fast) var(--ease)}
.tab::after{content:"";position:absolute;left:12px;right:12px;bottom:0;height:2px;border-radius:var(--r-line);background:var(--accent);transform:scaleX(0);transition:transform .25s var(--ease)}
.tab:hover{color:var(--text)}
.tab:hover::after{transform:scaleX(.35)}
.tab[aria-current="page"]{color:var(--accent);font-weight:var(--weight-medium)}
.tab[aria-current="page"]::after{transform:scaleX(1)}
.head-actions{display:flex;align-items:center;gap:8px;flex-shrink:0}
.lang-picker{position:relative}
.lang{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(--clear);font-size:var(--fs-small);color:var(--text-soft);cursor:pointer;transition:background-color var(--fast) var(--ease)}
.lang span{white-space:nowrap}
.lang:hover{background:var(--glass)}
.lang svg{width:15px;height:15px;flex-shrink:0}
.lang-panel{position:absolute;right:0;top:calc(100% + 10px);z-index:60;min-width:180px;padding:8px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-card);box-shadow:var(--shadow-float)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-small)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--panel-2)}
.btn-login{display:inline-flex;align-items:center;justify-content:center;height:36px;min-width:48px;padding:0 18px;border:1px solid var(--border);border-radius:var(--r-pill);background:var(--panel);font-size:var(--fs-small);font-weight:var(--weight-medium);color:var(--text);white-space:nowrap;box-shadow:var(--shadow-chip);transition:border-color var(--fast) var(--ease)}
.btn-login:hover{border-color:var(--muted)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:10px;background:var(--clear);color:var(--accent);border-radius:var(--r-pill)}
.menu-toggle svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.8;stroke-linecap:round}
.nav-drawer{display:none;position:fixed;left:0;right:0;top:var(--head-height);height:calc(100dvh - var(--head-height));max-height:calc(100dvh - var(--head-height));overflow-y:auto;overscroll-behavior:contain;padding:16px var(--gutter) 32px;background:var(--panel);z-index:52;border-top:1px solid var(--border)}
.nav-drawer a{display:flex;align-items:center;width:100%;min-height:48px;padding:12px 16px;border-radius:var(--r-card);color:var(--text-soft)}
.nav-drawer a:hover,.nav-drawer a[aria-current="page"]{color:var(--accent);background:var(--panel-2)}
.drawer-languages{border-top:1px solid var(--border);margin-top:16px;padding-top:16px}
.nav-veil{position:fixed;inset:var(--head-height) 0 0;background:var(--veil);z-index:51;border:0}
html.nav-open{overflow:hidden}

/* Shared footer */
.site-footer{background:var(--panel-2);border-top:1px solid var(--border);margin-top:64px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1.2fr;gap:64px;padding-top:56px;padding-bottom:48px}
.footer-brand p{max-width:28em;margin-top:20px;color:var(--text-soft);font-size:var(--fs-small)}
.footer-title{font-size:var(--fs-small);font-weight:var(--weight-medium);margin-bottom:16px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 20px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:28px;padding-block:2px;font-size:var(--fs-small);color:var(--text-soft);overflow-wrap:anywhere}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{text-decoration:underline;text-underline-offset:4px;color:var(--accent)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 24px;padding-bottom:24px}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;border-top:1px solid var(--border);padding-top:20px;padding-bottom:24px;font-size:var(--fs-micro);color:var(--muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:20px}
.footer-legal a{font-size:var(--fs-micro)}
@media(max-width:1439px){:root{--u:.9;--fs-display:62px}}
@media(max-width:1359px){:root{--u:.7;--fs-display:56px}.head-in{gap:20px}.tab{padding-inline:9px}}
@media(max-width:1199px){:root{--u:.62}.head-in{gap:14px}.tab{font-size:13px;padding-inline:7px}.lang{padding-inline:8px}}
@media(max-width:1023px){
  :root{--u:.58;--fs-display:52px}
  .tabs{display:none}.head-actions{margin-left:auto}.menu-toggle{display:inline-flex}.nav-drawer:not([hidden]){display:block}
  .footer-grid{gap:32px;grid-template-columns:1.2fr 1fr}.footer-brand{grid-column:1/-1}
}
@media(max-width:768px){
  :root{--pad-x:20px;--fs-display:40px;--fs-section:36px;--fs-h2:30px;--fs-h3:20px}
  .sec{padding-top:64px;padding-bottom:64px}
  .head-in{gap:12px}.head-actions{gap:4px;margin-left:auto}.lang{padding-inline:6px;font-size:13px}.btn-login{height:34px;padding:0 14px}
  .btn{min-height:44px;padding:0 22px;font-size:15px}.grid-three{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:minmax(0,1fr)}.footer-brand{grid-column:auto}
  .footer-bottom{align-items:flex-start;flex-direction:column}.card{padding:24px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none}
  .decorative-zone{overflow-x:clip;max-width:100%}
}
@media(max-width:374px){
  :root{--pad-x:16px}
  .brand{font-size:14px;gap:6px}.brand-mark{width:24px;height:24px}
  .head-in{gap:6px}.head-actions{gap:0}.btn-login{padding-inline:10px}.lang{font-size:12px;padding-inline:4px;gap:3px}
  .lang svg{display:none}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
  .btn:hover{transform:none}
}