:root{
  --c-bg:#E7EBF7;--c-panel:#F8F9FE;--c-groove:#D9DFF0;--c-border:#C9D1E6;
  --c-accent:#0A8494;--c-accent-dark:#06606C;--c-accent-light:#7FD3DC;--c-accent-soft:#D3EEF1;--c-accent-mist:#E6F5F7;
  --c-plum:#B44CE0;--c-plum-light:#D978E8;--c-ink:#10204A;--c-muted:#56627F;
  --c-success:#1E9E62;--c-warn:#D98A10;--c-error:#D6344A;--c-white:#FFFFFF;
  --c-hero-top:#EEF1FA;--c-hero-bottom:#DFE4F3;--c-on-ink:rgba(255,255,255,.92);
  --c-on-ink-line:rgba(255,255,255,.14);--c-ink-line:rgba(16,32,74,.08);
  --c-glass:rgba(248,249,254,.66);--c-highlight:rgba(255,255,255,.95);--c-accent-20:rgba(10,132,148,.2);
  --c-veil:rgba(16,32,74,.3);
  --shadow-tint:0 24px 48px rgba(10,132,148,.12);--shadow-tint-sm:0 12px 32px rgba(10,132,148,.12);--shadow-tint-key:0 8px 18px rgba(10,132,148,.2);
  --flag-red:#D7283A;--flag-white:#FFFFFF;--flag-blue:#2E3A78;--flag-black:#1B1D24;--flag-gold:#F2C230;--flag-edge:rgba(16,32,74,.14);
  --f-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei","Malgun Gothic",system-ui,sans-serif;
  --f-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Microsoft YaHei","Malgun Gothic",system-ui,sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --r-window:24px;--r-card:16px;--r-btn:12px;--r-cell:10px;--r-chip:8px;--r-pill:999px;--r-panel:28px;--r-menu:18px;--r-circle:50%;
  --gutter:32px;--content-width:1240px;--head-height:68px;--anchor-offset:88px;--toc-offset:88px;--toc-landing:160px;
  --fs-body:16px;--fs-small:14px;--fs-h1:66px;--fs-h2:44px;--fs-h3:24px;
  --fw-normal:400;--fw-medium:500;--fw-semibold:600;--fw-bold:700;--fw-display:800;
  --tracking-display:-.03em;--tracking-heading:-.02em;--ease-time:.16s;--reveal-time:.36s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
body{margin:0;background:var(--c-bg);color:var(--c-ink);font-family:var(--f-body);font-size:var(--fs-body);line-height:1.6;-webkit-font-smoothing:antialiased;overflow-x:clip}
html.nav-open{overflow:hidden}
[hidden]{display:none!important}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;padding:0;cursor:pointer}
button:disabled{cursor:not-allowed;opacity:.55}
img{max-width:100%;height:auto}
svg{flex-shrink:0}
p{margin:0}
ul{list-style:none;margin:0;padding:0}
h1,h2,h3{font-family:var(--f-display);font-weight:var(--fw-display);color:var(--c-ink);text-wrap:balance}
h1{font-size:var(--fs-h1);line-height:1.1;letter-spacing:var(--tracking-display)}
h2{font-size:var(--fs-h2);line-height:1.2;letter-spacing:var(--tracking-heading);margin:0 0 24px}
h3{font-size:var(--fs-h3);line-height:1.35;letter-spacing:var(--tracking-heading);margin:0 0 16px}
:focus-visible{outline:2px solid var(--c-accent);outline-offset:3px}
::selection{background:var(--c-accent-soft);color:var(--c-ink)}
.wrap{width:100%;max-width:calc(var(--content-width) + 64px);margin-inline:auto;padding-inline:var(--gutter)}
.wrap>*{min-width:0}
.section{padding-top:80px;padding-bottom:80px}
.section-head{text-align:center;max-width:800px;margin:0 auto 40px}
.section-head p{color:var(--c-muted);margin-bottom:24px}
.no-break{white-space:nowrap}
.muted{color:var(--c-muted)}
.mono{font-family:var(--f-mono);font-variant-numeric:tabular-nums}
.vh{position:absolute;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.svg-defs{position:absolute;width:0;height:0;overflow:hidden}
.icon{width:24px;height:24px;vertical-align:middle}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid>*{min-width:0}
.panel,.card{padding:24px;background:var(--c-panel);border-radius:var(--r-window);box-shadow:var(--shadow-tint-sm),inset 0 0 0 1px var(--c-highlight)}
.panel{border-radius:var(--r-panel)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:44px;padding:10px 22px;border-radius:var(--r-btn);font-weight:var(--fw-bold);flex-shrink:0;white-space:nowrap;transition:background var(--ease-time),transform var(--ease-time)}
.btn-primary{background:var(--c-accent);color:var(--c-white);box-shadow:var(--shadow-tint-sm)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--c-accent-dark)}
.btn-secondary{background:var(--c-ink);color:var(--c-white)}
.btn-secondary:hover{background:var(--c-accent-dark)}
.btn-outline{background:var(--c-panel);box-shadow:inset 0 0 0 1px var(--c-border);color:var(--c-ink)}
.btn-outline:hover{background:var(--c-accent-soft)}
.btn:active,.btn.is-pressed{transform:translateY(1px)}
.btn.is-focus{outline:2px solid var(--c-accent);outline-offset:3px}
.btn[aria-disabled="true"]{opacity:.55;pointer-events:none}
.prose{max-width:820px;margin-inline:auto;overflow-wrap:break-word}
.prose p,.prose ul,.prose ol{margin-top:16px;margin-bottom:24px}
.prose ul{list-style:disc;padding-left:24px}
.prose h2{margin-top:48px}
.prose h3{margin-top:32px}
.prose a:not(.btn){color:var(--c-accent-dark);text-decoration:underline;text-underline-offset:3px}
code{font-family:var(--f-mono);overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--c-groove);border-radius:var(--r-btn)}
pre code{overflow-wrap:normal;white-space:pre}
.reveal{transition:opacity var(--reveal-time),transform var(--reveal-time)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:120px;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status+*{margin-top:32px}
#server-status>*{min-width:0;max-width:100%}
.annc{position:relative;background:var(--c-ink);color:var(--c-on-ink)}
.annc-inner{min-height:44px;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:6px 18px;padding:6px 64px;font-size:var(--fs-small)}
.annc-text{display:flex;align-items:center;gap:10px;letter-spacing:.01em}
.annc-dot{width:6px;height:6px;border-radius:var(--r-circle);background:var(--c-accent-light);flex-shrink:0}
.annc-pill{display:inline-flex;align-items:center;justify-content:center;gap:6px;height:30px;padding:0 14px;border-radius:var(--r-pill);background:var(--c-accent-soft);color:var(--c-accent-dark);font-size:13px;font-weight:var(--fw-bold)}
.annc-pill svg{width:14px;height:14px}
.annc-pill:hover{background:var(--c-white)}
.annc-close{position:absolute;right:18px;top:50%;width:32px;height:32px;margin-top:-16px;display:grid;place-items:center;border-radius:var(--r-circle);color:var(--c-on-ink)}
.annc-close:hover{background:var(--c-on-ink-line)}
.annc-close svg{width:18px;height:18px}
.annc-toggle:checked+.annc{display:none}
.annc-toggle:focus-visible+.annc .annc-close{outline:2px solid var(--c-accent-light);outline-offset:2px}
.screen{position:relative;overflow-x:clip;max-width:100%;background:linear-gradient(180deg,var(--c-hero-top),var(--c-hero-bottom))}
#site-header{position:relative;z-index:40}
.site-head{position:relative;z-index:40;border-bottom:1px solid var(--c-ink-line)}
.head-inner{display:flex;align-items:center;gap:36px;min-height:var(--head-height);flex-wrap:nowrap}
.brand{display:flex;align-items:center;gap:10px;flex-shrink:0;min-height:32px}
.brand-mark{width:30px;height:30px}
.brand-en{font-family:var(--f-display);font-size:21px;font-weight:var(--fw-display);letter-spacing:var(--tracking-heading);color:var(--c-ink)}
.main-nav{flex:1;min-width:0}
.nav-list{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px}
.nav-link{display:inline-flex;align-items:center;justify-content:center;gap:4px;min-height:40px;padding:0 14px;border-radius:var(--r-pill);font-size:15px;font-weight:var(--fw-semibold);color:var(--c-ink);white-space:nowrap}
.nav-link:hover{background:var(--c-ink-line)}
.nav-link.is-active,.nav-menu a.is-active{background:var(--c-accent-soft);color:var(--c-accent-dark)}
.nav-link svg{width:14px;height:14px}
.nav-more{position:relative}
.nav-menu{position:absolute;top:100%;left:-8px;min-width:268px;margin-top:8px;padding:8px;border-radius:var(--r-menu);background:var(--c-panel);box-shadow:var(--shadow-tint),inset 0 0 0 1px var(--c-highlight);z-index:45}
.nav-menu a{display:block;padding:10px 12px;border-radius:var(--r-btn)}
.nav-menu a:hover{background:var(--c-bg)}
.nav-menu b{display:block;font-size:14.5px;font-weight:var(--fw-bold)}
.nav-menu small{display:block;margin-top:2px;font-size:12.5px;color:var(--c-muted)}
.head-tools{margin-left:auto;display:flex;align-items:center;gap:10px;flex-shrink:0}
.lang-control{position:relative}
.lang-btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:40px;min-width:44px;width:auto;padding:0 12px;border-radius:var(--r-pill);font-size:var(--fs-small);font-weight:var(--fw-semibold);color:var(--c-muted);white-space:nowrap}
.lang-btn span{white-space:nowrap}
.lang-btn:hover{background:var(--c-ink-line)}
.lang-btn svg{width:16px;height:16px}
.lang-btn .chev{width:13px;height:13px}
.lang-panel{position:absolute;right:0;top:calc(100% + 8px);z-index:60;width:190px;padding:8px;border-radius:var(--r-menu);background:var(--c-panel);box-shadow:var(--shadow-tint)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-chip)}
.lang-panel a:hover,.lang-panel a[aria-current]{background:var(--c-accent-soft);color:var(--c-accent-dark)}
.login-btn{display:inline-flex;align-items:center;justify-content:center;min-height:42px;padding:0 24px;border-radius:var(--r-btn);background:var(--c-panel);box-shadow:inset 0 0 0 1.5px var(--c-ink);font-size:15px;font-weight:var(--fw-bold);color:var(--c-ink);white-space:nowrap}
.login-btn:hover{background:var(--c-ink);color:var(--c-white)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:4px;min-width:44px;min-height:44px;border-radius:var(--r-btn)}
.menu-line{display:block;width:20px;height:2px;background:currentColor}
.mobile-drawer{display:none}
.nav-veil{display:none}
.site-footer{padding-top:56px;padding-bottom:32px;background:var(--c-panel);border-top:1px solid var(--c-border)}
.footer-grid{display:grid;grid-template-columns:1.2fr 1fr 1fr 1fr;gap:40px}
.footer-grid>*{min-width:0}
.footer-brand p{margin-top:18px;max-width:27em;color:var(--c-muted);font-size:var(--fs-small)}
.footer-title{font-weight:var(--fw-bold);margin-bottom:16px}
.footer-links{display:grid;gap:4px}
.footer-links a{display:inline-flex;align-items:center;min-height:32px;color:var(--c-muted);font-size:var(--fs-small)}
.footer-links a:hover{color:var(--c-accent-dark);text-decoration:underline}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:16px;margin-top:40px;padding-top:24px;border-top:1px solid var(--c-border);font-size:var(--fs-small);color:var(--c-muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:16px}
.footer-legal a{display:inline-flex;align-items:center;min-height:24px}
@media(max-width:1180px){
  .head-inner{gap:20px}
  .nav-link{padding-inline:10px}
  .lang-btn{padding-inline:8px}
}
@media(max-width:960px){
  .main-nav{display:none}
  .head-inner{gap:12px}
  .head-tools{margin-left:auto}
  .menu-toggle{display:flex}
  .site-head{background:var(--c-hero-top)}
  .mobile-drawer{position:fixed;top:var(--drawer-top,var(--head-height));left:0;right:0;height:calc(100dvh - var(--drawer-top,var(--head-height)));max-height:calc(100dvh - var(--drawer-top,var(--head-height)));z-index:35;padding:16px var(--gutter) 32px;background:var(--c-panel);overflow-y:auto;overscroll-behavior:contain}
  .mobile-drawer:not([hidden]){display:block}
  .mobile-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;border-radius:var(--r-btn);font-weight:var(--fw-semibold)}
  .mobile-drawer a:hover,.mobile-drawer a.is-active,.mobile-drawer a[aria-current]{background:var(--c-accent-soft);color:var(--c-accent-dark)}
  .drawer-languages{margin-top:20px;padding-top:16px;border-top:1px solid var(--c-border)}
  .nav-veil{position:fixed;inset:var(--drawer-top,var(--head-height)) 0 0;z-index:30;background:var(--c-veil)}
  .nav-veil:not([hidden]){display:block}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media(max-width:768px){
  :root{--gutter:16px;--fs-h1:40px;--fs-h2:32px;--fs-h3:22px}
  .section{padding-top:48px;padding-bottom:48px}
  .grid{grid-template-columns:minmax(0,1fr)}
  .annc-inner{padding:8px 52px 8px 16px;font-size:12.5px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,.stage{transform:none}
  [data-hero-visual],.decor-section,.screen{max-width:100%;overflow-x:clip}
  .footer-grid{grid-template-columns:minmax(0,1fr);gap:28px}
  .head-inner{gap:8px}
  .head-tools{gap:4px;margin-left:auto}
  .brand{gap:7px}
  .brand-en{font-size:18px}
  .brand-mark{width:26px;height:26px}
  .login-btn{padding-inline:14px;font-size:var(--fs-small)}
  .lang-txt{display:none}
  .lang-btn{padding-inline:8px}
  .lang-btn .chev{display:none}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition:none!important;animation:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}