:root{
  color-scheme:light;
  --bg:#F9F8FB;
  --bg-panel:#FFFFFF;
  --bg-panel-2:#F1EFF6;
  --border:#E4E1EC;
  --accent:#7E22F2;
  --accent-dark:#5B10BE;
  --accent-2:#9454F8;
  --lilac:#C9B2FB;
  --lilac-pale:#E9DDFE;
  --canvas-top:#F4EEFE;
  --text:#0F0E14;
  --text-muted:#5E5B6B;
  --success:#14935A;
  --warn:#C77A0E;
  --error:#D2333F;
  --ink:#0F0E14;
  --ink-2:#2A2733;
  --capsule:#3A3741;
  --on-dark:#FFFFFF;
  --ann-from:#1E0838;
  --ann-to:#B98AF8;
  --clear:rgba(249,248,251,0);
  --grid-line:rgba(15,14,20,.035);
  --atmo:rgba(126,34,242,.05);
  --accent-tint:rgba(126,34,242,.06);
  --accent-ring:rgba(126,34,242,.16);
  --success-ring:rgba(20,147,90,.16);
  --hi:rgba(255,255,255,1);
  --veil:rgba(15,14,20,.32);
  --shadow-panel:0 1px 2px rgba(15,14,20,.04),0 28px 72px -18px rgba(126,34,242,.10),0 12px 28px -12px rgba(126,34,242,.10);
  --shadow-capsule:0 2px 4px rgba(15,14,20,.10),0 18px 36px -12px rgba(91,16,190,.22);
  --flag-red:#D0263A;
  --flag-blue:#1E3F95;
  --flag-navy:#2B2F6B;
  --flag-white:#FFFFFF;
  --flag-edge:rgba(15,14,20,.14);
  --r-btn:2px;
  --r-sm:4px;
  --r-md:6px;
  --r-round:50%;
  --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,'SFMono-Regular',Menlo,Consolas,'Noto Sans SC',monospace;
  --fs-xs:11px;
  --fs-label:12px;
  --fs-small:13px;
  --fs-kicker:13.5px;
  --fs-meta:14px;
  --fs-nav:15px;
  --fs-body:16px;
  --fs-button:17px;
  --fs-icon:18px;
  --fs-lede:19px;
  --fs-brand:20px;
  --fs-sub:22px;
  --fs-h3:clamp(22px,2.4vw,28px);
  --fs-h2:clamp(28px,3.4vw,42px);
  --fs-h1:clamp(52px,4.6vw,66px);
  --fs-h1-mobile:clamp(28px,9vw,40px);
  --weight-normal:400;
  --weight-medium:500;
  --tracking-title:-.03em;
  --tracking-cjk:-.02em;
  --tracking-label:.06em;
  --leading-body:1.6;
  --leading-title:1.1;
  --gutter:24px;
  --wrap-width:1280px;
  --head-width:1440px;
  --head-height:64px;
  --drawer-top:104px;
  --toc-offset:16px;
  --section-offset:96px;
  --ease-ui:cubic-bezier(.2,.7,.2,1);
  --duration-reveal:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-padding-top:80px;scroll-behavior:smooth}
html.nav-open{overflow:hidden}
body{
  margin:0;font-family:var(--font-body);font-size:var(--fs-body);line-height:var(--leading-body);
  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);
  background-size:32px 32px;-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{max-width:100%;height:auto}
svg{vertical-align:middle}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
::selection{background:var(--lilac-pale);color:var(--text)}
h1,h2,h3{font-family:var(--font-display);font-weight:var(--weight-normal);letter-spacing:var(--tracking-title);text-wrap:balance;overflow-wrap:break-word}
:lang(zh-CN) h1,:lang(zh-CN) h2,:lang(zh-CN) h3{letter-spacing:var(--tracking-cjk)}
h1{font-size:var(--fs-h1);line-height:var(--leading-title)}
h2{font-size:var(--fs-h2);line-height:1.2;margin:0 0 24px}
h3{font-size:var(--fs-h3);line-height:1.3;margin:0 0 16px}
p{margin:0 0 20px}
strong{font-weight:var(--weight-medium)}
code,kbd,pre{font-family:var(--font-mono)}
code{overflow-wrap:anywhere;font-size:.9em}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--bg-panel-2);border:1px solid var(--border);border-radius:var(--r-sm)}
pre code{overflow-wrap:normal;white-space:pre}
hr{border:0;border-top:1px solid var(--border);margin:32px 0}
.no-break{white-space:nowrap}
.wrap{width:100%;max-width:var(--wrap-width);margin-inline:auto;padding-inline:var(--gutter)}
.sec{padding-top:80px;padding-bottom:80px}
.stack>*+*{margin-top:24px}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono);font-size:var(--fs-label);letter-spacing:var(--tracking-label);text-transform:uppercase}
.panel,.card{min-width:0;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-md);box-shadow:inset 0 1px 0 var(--hi),var(--shadow-panel);padding:24px}
.grid-2,.grid-3,.grid-5{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-5{grid-template-columns:repeat(5,minmax(0,1fr))}
.grid-2>*,.grid-3>*,.grid-5>*{min-width:0}
.prose{max-width:76ch;min-width:0}
.prose h2{margin-top:56px}
.prose h3{margin-top:32px}
.prose a:not(.btn){color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
.prose li{margin-bottom:8px}
.prose img{display:block}
.prose blockquote{margin-inline:0}
.decor-region{position:relative;overflow-x:clip;max-width:100%}
.reveal{transition:opacity var(--duration-reveal) var(--ease-ui),transform var(--duration-reveal) var(--ease-ui)}
.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%;overflow:hidden;margin-top:24px;margin-bottom:32px}
#server-status+*{margin-top:32px}
#server-status>*{min-width:0;max-width:100%}

/* Notice and shared navigation */
.notice{background:linear-gradient(90deg,var(--ann-from) 0%,var(--accent-dark) 56%,var(--ann-to) 100%);color:var(--on-dark)}
.notice-in{min-height:40px;display:flex;align-items:center;justify-content:center;flex-wrap:wrap;gap:6px 16px;padding:6px 20px;font-size:var(--fs-meta);letter-spacing:-.005em}
.notice-btn{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:28px;padding:4px 12px;background:var(--ink);color:var(--on-dark);border-radius:var(--r-btn);font-size:var(--fs-small)}
.notice-btn:hover{background:var(--ink-2)}
.chev{font-family:var(--font-mono)}
.site-head{position:relative;z-index:50;background:var(--bg-panel);border-bottom:1px solid var(--border)}
.head-in{position:relative;max-width:var(--head-width);margin:0 auto;min-height:var(--head-height);display:flex;align-items:stretch;padding-left:32px}
.brand{display:flex;align-items:center;gap:10px;margin-right:44px;font-family:var(--font-display);font-size:var(--fs-brand);letter-spacing:-.02em;color:var(--text);flex-shrink:0}
.brand-mark{width:30px;height:30px;display:block;flex-shrink:0}
.nav{display:flex;align-items:center;flex:1;min-width:0}
.nav-list{list-style:none;margin:0;padding:0;display:flex;align-items:center;font-size:var(--fs-nav);color:var(--text-muted);white-space:nowrap}
.nav-list li{display:flex;align-items:center}
.nav-list li+li::before{content:"·";padding:0 11px;color:var(--lilac)}
.nav-list a{display:inline-flex;align-items:center;min-height:44px}
.nav-list a:hover{color:var(--text)}
.nav-list a[aria-current="page"]{color:var(--text);text-decoration:underline;text-decoration-color:var(--accent);text-decoration-thickness:2px;text-underline-offset:8px}
.head-tools{display:flex;align-items:stretch;margin-left:auto;flex-shrink:0}
.language-control{position:relative;display:flex}
.lang{display:flex;align-items:center;justify-content:center;gap:7px;width:auto;min-width:44px;padding:0 22px;border:0;border-left:1px solid var(--border);background:var(--bg-panel);color:var(--text-muted);font:inherit;font-size:var(--fs-meta);cursor:pointer}
.lang span{white-space:nowrap}
.lang svg{width:16px;height:16px;flex-shrink:0}
.caret{font-size:var(--fs-xs)}
.language-panel{position:absolute;right:0;top:100%;z-index:65;min-width:180px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-sm);box-shadow:var(--shadow-panel)}
.language-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;font-size:var(--fs-meta)}
.language-panel a:hover,.language-panel a[aria-current="true"]{background:var(--bg-panel-2);color:var(--accent-dark)}
.login{display:inline-flex;align-items:center;justify-content:center;padding:0 34px;min-height:44px;background:var(--ink);color:var(--on-dark);font-size:var(--fs-nav);white-space:nowrap}
.login:hover{background:var(--ink-2)}
.menu-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:5px;min-width:44px;min-height:44px;border:0;border-left:1px solid var(--border);background:var(--bg-panel);color:var(--text)}
.menu-line{display:block;width:20px;height:2px;background:currentColor}
.menu-toggle[aria-expanded="true"] .menu-line:first-child{transform:translateY(7px) rotate(45deg)}
.menu-toggle[aria-expanded="true"] .menu-line:nth-child(2){opacity:0}
.menu-toggle[aria-expanded="true"] .menu-line:last-child{transform:translateY(-7px) rotate(-45deg)}
.nav-drawer{display:none}
.nav-veil{display:none}
.drawer-languages{border-top:1px solid var(--border);margin-top:16px;padding-top:16px}
.ic-line{fill:none;stroke:currentColor;stroke-width:1.4}

/* Buttons */
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin-top:36px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:12px;min-height:52px;padding:10px 26px;border:1px solid var(--ink);border-radius:var(--r-btn);font-family:var(--font-body);font-size:var(--fs-button);line-height:1.4;letter-spacing:-.01em;max-width:100%;text-align:center}
.btn-solid,.btn-primary{background:var(--ink);color:var(--on-dark)}
.btn-solid:hover,.btn-primary:hover,.btn.is-hover{background:var(--ink-2);color:var(--on-dark)}
.btn-line,.btn-secondary{background:var(--bg-panel);color:var(--ink)}
.btn-line:hover,.btn-secondary:hover{background:var(--bg-panel-2)}
.btn:active,.btn.is-active{background:var(--accent-dark);border-color:var(--accent-dark);color:var(--on-dark)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--bg-panel-2);border-color:var(--border);color:var(--text-muted);cursor:not-allowed}
.btn.is-focus{outline:2px solid var(--accent);outline-offset:3px}
.btn .chev{font-size:var(--fs-icon);line-height:1}

/* Footer */
.site-foot{background:var(--bg-panel);border-top:1px solid var(--border)}
.foot-grid{display:grid;grid-template-columns:1.1fr 1fr 1fr;gap:48px;padding-top:56px;padding-bottom:40px}
.foot-brand .brand{margin:0 0 20px;min-height:40px}
.foot-brand p{max-width:30em;color:var(--text-muted);font-size:var(--fs-meta)}
.foot-title{font-family:var(--font-mono);font-weight:var(--weight-normal);font-size:var(--fs-label);letter-spacing:var(--tracking-label);color:var(--text-muted);margin:0 0 16px}
.foot-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 16px;list-style:none;margin:0;padding:0}
.foot-links a,.foot-languages a,.foot-legal a{display:inline-flex;align-items:center;min-height:32px;font-size:var(--fs-meta)}
.foot-links a:hover,.foot-languages a:hover,.foot-legal a:hover{color:var(--accent-dark);text-decoration:underline;text-underline-offset:4px}
.foot-languages{display:flex;flex-wrap:wrap;gap:8px 24px;padding-top:20px;padding-bottom:20px;border-top:1px solid var(--border)}
.foot-languages a[aria-current="true"]{color:var(--accent-dark)}
.foot-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px 24px;padding-top:20px;padding-bottom:24px;border-top:1px solid var(--border);font-size:var(--fs-small);color:var(--text-muted)}
.foot-bottom p{margin:0}
.foot-legal{display:flex;flex-wrap:wrap;gap:8px 24px}

@media(max-width:1320px){
  .brand{margin-right:24px}
  .nav-list{font-size:var(--fs-meta)}
  .nav-list li+li::before{padding-inline:8px}
  .lang{padding-inline:16px}
  .login{padding-inline:24px}
}
@media(max-width:1180px){
  .nav-list li+li::before{padding-inline:6px}
  .head-in{padding-left:20px}
  .brand{margin-right:18px}
}
@media(max-width:1080px){
  .head-in{flex-wrap:nowrap;min-height:56px}
  .brand{min-height:56px}
  .nav{display:none}
  .head-tools{margin-left:auto}
  .menu-toggle{display:flex}
  .nav-drawer{position:fixed;display:block;z-index:60;left:0;right:0;top:var(--drawer-top);height:calc(100dvh - var(--drawer-top));max-height:calc(100dvh - var(--drawer-top));overflow-y:auto;overscroll-behavior:contain;background:var(--bg-panel);padding:16px var(--gutter) 32px;border-top:1px solid var(--border)}
  .nav-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;border-bottom:1px solid var(--border)}
  .nav-drawer a[aria-current]{color:var(--accent-dark);background:var(--bg-panel-2)}
  .nav-veil{display:block;position:fixed;z-index:55;inset:var(--drawer-top) 0 0;background:var(--veil);border:0;width:100%}
  .grid-5{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media(max-width:768px){
  h1{font-size:var(--fs-h1-mobile)}
  .sec{padding-top:48px;padding-bottom:48px}
  .grid-3,.grid-2{grid-template-columns:minmax(0,1fr)}
  .grid-5{grid-template-columns:repeat(2,minmax(0,1fr))}
  .btn{min-height:48px;padding:10px 22px;font-size:var(--fs-body)}
  .cta-row{margin-top:28px}
  .foot-grid{grid-template-columns:minmax(0,1fr);gap:32px}
  .decor-region{max-width:100%}
}
@media(max-width:640px){
  :root{--gutter:20px}
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none!important}
  .head-in{padding-left:16px}
  .brand{gap:7px;margin-right:8px;font-size:var(--fs-icon)}
  .brand-mark{width:26px;height:26px}
  .lang{padding-inline:10px;font-size:var(--fs-small);gap:5px}
  .lang svg{display:none}
  .login{padding-inline:16px;font-size:var(--fs-meta)}
  .head-tools{margin-left:auto}
  .panel,.card{padding:20px}
}
@media(max-width:360px){
  :root{--gutter:16px}
  .brand{font-size:var(--fs-body)}
  .brand-mark{width:24px;height:24px}
  .lang{padding-inline:7px}
  .login{padding-inline:12px}
  .grid-5{grid-template-columns:minmax(0,1fr)}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}