:root{
  color-scheme:light;
  --bg:#FBFBFD;
  --panel:#FFFFFF;
  --panel-2:#F2F4F8;
  --border:#DCDFE6;
  --accent:#1D4EF5;
  --accent-dark:#1235B8;
  --accent-tint:rgba(29,78,245,.06);
  --violet:#6A4CF0;
  --text:#15171F;
  --muted:#5A5F6C;
  --success:#1E8A52;
  --warn:#B8761A;
  --error:#CF2A3B;
  --on-accent:#FFFFFF;
  --transparent:transparent;
  --ambient-top:rgba(29,78,245,.04);
  --ambient-bottom:rgba(106,76,240,.075);
  --win-top:#2C46C8;
  --win-bottom:#6E7FE6;
  --violet-glow:rgba(106,76,240,.62);
  --win-inner-edge:rgba(255,255,255,.14);
  --glass-top-a:rgba(255,255,255,.60);
  --glass-top-b:rgba(214,224,255,.34);
  --glass-front-a:rgba(255,255,255,.24);
  --glass-front-b:rgba(190,202,255,.10);
  --glass-right-a:rgba(206,214,255,.18);
  --glass-right-b:rgba(28,40,150,.30);
  --glass-center-a:rgba(255,255,255,.40);
  --glass-center-b:rgba(160,142,255,.24);
  --glass-line:rgba(255,255,255,.40);
  --glass-hilite:rgba(255,255,255,.88);
  --glass-glow:rgba(255,255,255,.55);
  --glass-sheen:rgba(255,255,255,.26);
  --glass-text-shadow:rgba(14,26,120,.40);
  --on-glass:#FFFFFF;
  --on-glass-soft:rgba(255,255,255,.80);
  --core-a:rgba(29,78,245,.92);
  --core-b:rgba(106,76,240,.95);
  --core-c:rgba(178,166,255,.85);
  --core-fade:rgba(106,76,240,0);
  --ground:rgba(12,28,128,.52);
  --ground-fade:rgba(12,28,128,0);
  --ink-veil:rgba(21,23,31,.80);
  --veil:rgba(21,23,31,.32);
  --flag-red:#CF2A3B;
  --flag-white:#FFFFFF;
  --flag-navy:#24357F;
  --flag-edge:rgba(21,23,31,.20);
  --shadow-window:0 44px 100px -12px rgba(29,78,245,.12),0 14px 36px -10px rgba(29,78,245,.12);
  --shadow-float:0 18px 44px rgba(29,78,245,.14),0 2px 6px rgba(21,23,31,.06);
  --shadow-card-hover:0 14px 34px rgba(29,78,245,.10);
  --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","Malgun Gothic",system-ui,sans-serif;
  --font-mono:"JetBrains Mono","SFMono-Regular",Consolas,"Liberation Mono",Menlo,monospace;
  --weight-regular:400;
  --weight-medium:500;
  --weight-strong:600;
  --text-xs:11px;
  --text-sm:12px;
  --text-label:13px;
  --text-nav:14px;
  --text-card:15px;
  --text-base:16px;
  --body:17px;
  --text-lg:20px;
  --text-xl:24px;
  --h2:36px;
  --h3:24px;
  --h1:64px;
  --radius:0;
  --radius-round:50%;
  --tracking-title:-.02em;
  --tracking-label:.02em;
  --line-body:1.6;
  --line-title:1.1;
  --gutter:40px;
  --content-max:1440px;
  --reading-max:820px;
  --header-h:64px;
  --anchor-offset:80px;
  --toc-offset:144px;
  --s:312px;
  --win-h:620px;
  --ease:ease;
  --duration:.2s;
  --reveal-duration:.35s;
  --space-section:72px;
}
*,*::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(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--text-base);line-height:var(--line-body);-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit;border-radius:var(--radius)}
button{cursor:pointer}
button,a{-webkit-tap-highlight-color:var(--accent-tint)}
button{border:1px solid var(--border)}
[hidden]{display:none!important}
ul,ol{padding-left:1.5em}
h1,h2,h3,h4,p,figure,blockquote{margin:0}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:var(--weight-regular);overflow-wrap:break-word}
h1{font-size:var(--h1);line-height:var(--line-title);letter-spacing:var(--tracking-title)}
h2{font-size:var(--h2);line-height:1.25;letter-spacing:var(--tracking-title)}
h3{font-size:var(--h3);line-height:1.35}
p{overflow-wrap:break-word}
strong{font-weight:var(--weight-strong)}
:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
::selection{background:var(--accent);color:var(--on-accent)}
.wrap{width:100%;max-width:var(--content-max);padding-inline:var(--gutter);margin-inline:auto}
.section{padding-top:var(--space-section);padding-bottom:var(--space-section)}
.section-heading{margin-bottom:32px}
.section-heading p{margin-top:16px;max-width:var(--reading-max);color:var(--muted)}
.reading-wrap{width:100%;max-width:var(--reading-max);margin-inline:auto}
.grid{display:grid;gap:24px}
.grid-2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-4{grid-template-columns:repeat(4,minmax(0,1fr))}
.grid>*,.hero-grid>*,.footer-grid>*,.header-inner>*{min-width:0}
.panel,.card{background:var(--panel);border:1px solid var(--border);border-radius:var(--radius);padding:24px}
.panel-inset{background:var(--panel-2)}
.card-link{position:relative;transition:box-shadow var(--duration)}
.card-link:hover{box-shadow:var(--shadow-card-hover)}
.muted{color:var(--muted)}
.mono,.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.no-break{white-space:nowrap}
.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}
.ico{fill:none;stroke:currentColor;stroke-width:1.5;stroke-linecap:square;stroke-linejoin:miter}
.fw{fill:var(--flag-white)}
.fr{fill:var(--flag-red)}
.fn{fill:var(--flag-navy)}
.fedge{fill:none;stroke:var(--flag-edge);stroke-width:1}
.prose{font-size:var(--body);line-height:1.85;min-width:0}
.prose p+p,.prose ul,.prose ol,.prose pre,.prose blockquote{margin-top:20px}
.prose h2{margin-top:56px;margin-bottom:24px}
.prose h3{margin-top:32px;margin-bottom:16px}
.prose a:not(.btn){color:var(--accent);text-decoration:underline;text-underline-offset:3px}
code{font-family:var(--font-mono);font-size:.88em;overflow-wrap:anywhere;background:var(--panel-2);padding:2px 5px}
pre{max-width:100%;overflow-x:auto;background:var(--panel-2);border:1px solid var(--border);padding:20px;tab-size:2}
pre code{padding:0;background:var(--transparent);overflow-wrap:normal;white-space:pre}
table{border-collapse:collapse}
th,td{text-align:left;vertical-align:top}
.btn{display:inline-flex;align-items:center;justify-content:space-between;gap:24px;min-width:200px;min-height:56px;padding:14px 16px 14px 20px;font-size:var(--text-base);font-weight:var(--weight-regular);border:1px solid var(--transparent);border-radius:var(--radius);transition:background-color var(--duration),color var(--duration),border-color var(--duration);flex-shrink:0;white-space:nowrap}
.btn svg{width:20px;height:20px;transition:transform var(--duration)}
.btn-primary{background:var(--accent);color:var(--on-accent)}
.btn-primary:hover,.btn-primary.is-hover{background:var(--accent-dark)}
.btn-primary:hover svg{transform:translateX(3px)}
.btn-secondary{background:var(--panel);color:var(--accent);border-color:var(--accent)}
.btn-secondary:hover,.btn-secondary.is-hover{background:var(--accent-tint);color:var(--accent-dark);border-color:var(--accent-dark)}
.btn:active,.btn.is-active{box-shadow:inset 0 0 0 2px currentColor}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.5;cursor:not-allowed}
.btn-small{min-width:0;min-height:44px;font-size:var(--text-nav);padding:10px 16px}
.cta-row{display:flex;gap:16px;margin-top:32px;flex-wrap:wrap}
.text-link{display:inline-flex;align-items:center;gap:12px;color:var(--accent);min-height:24px}
.text-link:hover{text-decoration:underline;text-underline-offset:4px}
.text-link svg{width:20px;height:20px}
.site-header,#site-header{position:sticky;top:0;z-index:60;background:var(--panel);border-bottom:1px solid var(--border)}
.header-inner{display:flex;align-items:center;flex-wrap:nowrap;height:var(--header-h)}
.brand{display:flex;align-items:center;gap:10px;height:32px;padding-right:24px;margin-right:12px;border-right:1px solid var(--border);font-family:var(--font-display);font-size:19px;font-weight:var(--weight-medium);letter-spacing:-.01em;flex:none}
.brand img{width:30px;height:30px;flex:none}
.brand-zh{font-weight:var(--weight-regular);color:var(--muted)}
.desktop-nav{flex:1;min-width:0}
.nav-list{display:flex;align-items:center;list-style:none;margin:0;padding:0;height:var(--header-h);gap:0}
.nav-list li{height:100%;flex-shrink:0}
.nav-link{position:relative;display:flex;align-items:center;gap:7px;height:100%;min-height:44px;padding:0 12px;font-size:var(--text-nav);color:var(--muted);white-space:nowrap;transition:color var(--duration),background-color var(--duration)}
.nav-link svg{width:16px;height:16px}
.nav-link:hover{color:var(--text);background:var(--panel-2)}
.nav-link[aria-current="page"]{color:var(--text)}
.nav-link[aria-current="page"]::after{content:"";position:absolute;left:12px;right:12px;bottom:-1px;height:2px;background:var(--accent)}
.header-tools{margin-left:auto;display:flex;align-items:center;gap:12px;flex:none}
.lang-select{position:relative}
.lang-btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:36px;min-width:44px;width:auto;padding:0 10px;border:0;background:var(--transparent);font-size:var(--text-nav);color:var(--muted);white-space:nowrap}
.lang-btn span{white-space:nowrap}
.lang-btn svg{width:16px;height:16px}
.lang-btn:hover{background:var(--panel-2);color:var(--text)}
.lang-panel{position:absolute;right:0;top:calc(100% + 12px);z-index:75;min-width:180px;background:var(--panel);border:1px solid var(--border);box-shadow:var(--shadow-float);padding:6px}
.lang-panel a{display:flex;align-items:center;min-height:44px;width:100%;padding:8px 12px;font-size:var(--text-nav)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{color:var(--accent);background:var(--panel-2)}
.login-btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:36px;padding:6px 16px;border:1px solid var(--text);font-size:var(--text-nav);white-space:nowrap;transition:background-color var(--duration),color var(--duration)}
.login-btn svg{width:16px;height:16px}
.login-btn:hover{background:var(--text);color:var(--panel)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;padding:10px;background:var(--panel);border:1px solid var(--border)}
.menu-toggle svg{width:22px;height:22px}
.mobile-drawer{display:none;position:fixed;top:var(--header-h);left:0;right:0;z-index:55;height:calc(100dvh - var(--header-h));max-height:calc(100dvh - var(--header-h));overflow-y:auto;overscroll-behavior:contain;background:var(--panel);padding:16px var(--gutter) 32px}
.mobile-drawer a{display:flex;align-items:center;gap:12px;width:100%;min-height:48px;padding:12px 16px;border-bottom:1px solid var(--border);font-size:var(--text-base)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current]{color:var(--accent);background:var(--panel-2)}
.mobile-drawer svg{width:18px;height:18px}
.drawer-languages{margin-top:24px;border-top:2px solid var(--accent);padding-top:12px}
.nav-veil{position:fixed;top:var(--header-h);inset-inline:0;bottom:0;z-index:50;background:var(--veil);border:0;width:100%;padding:0}
html.nav-open{overflow:hidden}
.site-footer{background:var(--panel-2);border-top:1px solid var(--border);padding-top:56px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1.2fr 1fr;gap:40px}
.footer-brand{display:inline-flex;align-items:center;gap:10px;font-size:var(--text-lg);font-weight:var(--weight-medium);min-height:32px}
.footer-brand img{width:32px;height:32px}
.footer-intro{margin-top:20px;max-width:320px;color:var(--muted);font-size:var(--text-nav)}
.footer-title{font-size:var(--text-nav);font-weight:var(--weight-strong);padding-bottom:12px;border-bottom:1px solid var(--border);margin-bottom:12px}
.footer-links{list-style:none;padding:0;margin:0;display:grid;gap:4px}
.footer-links a{display:inline-flex;align-items:center;min-height:28px;font-size:var(--text-nav);color:var(--muted)}
.footer-links a:hover{color:var(--accent);text-decoration:underline;text-underline-offset:3px}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-top:40px;padding-top:20px;border-top:1px solid var(--border);font-size:var(--text-sm);color:var(--muted)}
.footer-legal{display:flex;gap:20px;flex-wrap:wrap}
.footer-legal a{display:inline-flex;align-items:center;min-height:24px}
.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}
.decor-section{position:relative;overflow-x:clip;max-width:100%}
#server-status{position:relative;display:block;width:100%;min-width:0;min-height:120px;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status+*{margin-top:24px}
[data-counter]{display:inline-block;min-width:3ch;font-variant-numeric:tabular-nums;font-family:var(--font-mono)}
@media(min-width:1181px) and (max-width:1360px){
  .nav-list{gap:2px}
  .nav-link{padding-inline:7px;gap:5px;font-size:var(--text-label)}
  .brand{padding-right:16px;margin-right:8px}
  .header-tools{gap:8px}
}
@media(max-width:1180px){
  .desktop-nav{display:none}
  .header-tools{margin-left:auto}
  .menu-toggle{display:inline-flex}
  html.nav-open .mobile-drawer{display:block}
}
@media(max-width:768px){
  :root{--gutter:20px;--h1:40px;--h2:30px;--h3:22px;--space-section:48px;--win-h:360px}
  .grid-3,.grid-4{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px}
  .brand{padding-right:0;border:0;margin-right:0}
}
@media(max-width:640px){
  :root{--body:16px}
  .no-break{white-space:normal}
  .grid-2,.grid-3,.grid-4{grid-template-columns:minmax(0,1fr)}
  .cta-row{flex-direction:column}
  .btn{width:100%;min-width:0}
  .header-tools{gap:6px;margin-left:auto}
  .brand{font-size:var(--text-base);gap:7px}
  .brand img{width:26px;height:26px}
  .login-btn{padding:6px 10px;font-size:var(--text-label)}
  .login-btn svg{display:none}
  .lang-btn{font-size:var(--text-sm);gap:4px;padding-inline:6px}
  .lang-btn svg{width:14px;height:14px}
  .menu-toggle{padding:8px}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .tilt,.decor-tilt{transform:none;max-width:100%}
  .decor-section{max-width:100%}
}
@media(max-width:359px){
  :root{--gutter:16px}
  .header-tools{gap:3px}
  .lang-btn{padding-inline:3px}
  .brand{gap:5px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
  *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
}