:root{
  --bg:#F9EFDC;
  --bg-panel:#FFFBF3;
  --bg-panel-2:#F2E6D0;
  --border:#E3D5BC;
  --accent:#0B6CD8;
  --accent-dark:#0A4E9E;
  --accent-light:#3A8CF0;
  --accent-soft:#E4EEFB;
  --accent-soft-2:#D6E5F8;
  --text:#2A2117;
  --text-soft:#4A3C2C;
  --text-muted:#6E604E;
  --text-faint:#9C8C74;
  --success:#2E8A4E;
  --warn:#C7851A;
  --error:#C23A2B;
  --white:#FFFFFF;
  --hero-top:#FCF6EA;
  --hero-bottom:#F3E7D2;
  --wall-top:#F4DDB6;
  --wall-bottom:#E9C99A;
  --chrome-dot:#D4C2A3;
  --chrome-bg:rgba(255,251,243,.74);
  --chrome-line:rgba(42,33,23,.08);
  --flag-red:#CF2E36;
  --flag-blue:#24367C;
  --flag-white:#FFFFFF;
  --flag-ring:rgba(42,33,23,.18);
  --sun-band:rgba(255,248,232,.44);
  --sun-core:rgba(255,246,226,.58);
  --pillar:rgba(255,247,230,.62);
  --wall-shade:rgba(150,98,40,.16);
  --glass:rgba(255,251,243,.62);
  --glass-weak:rgba(255,251,243,.5);
  --glass-line:rgba(255,255,255,.58);
  --glass-edge:rgba(255,255,255,.88);
  --ink-glass:rgba(42,33,23,.76);
  --ink-deep:rgba(20,14,8,.42);
  --ink-a05:rgba(42,33,23,.05);
  --ink-a10:rgba(42,33,23,.10);
  --veil:rgba(42,33,23,.28);
  --ring-1:rgba(58,140,240,.24);
  --ring-1-line:rgba(255,255,255,.42);
  --ring-2:rgba(58,140,240,.12);
  --ring-2-line:rgba(58,140,240,.22);
  --hi-on-blue:rgba(255,255,255,.36);
  --hi-knob:rgba(255,255,255,.52);
  --accent-deep:rgba(10,78,158,.45);
  --accent-a12:rgba(11,108,216,.12);
  --accent-a30:rgba(11,108,216,.30);
  --accent-a40:rgba(11,108,216,.40);
  --success-a25:rgba(46,138,78,.28);
  --shadow-win:0 2px 6px rgba(42,33,23,.05),0 30px 60px -32px rgba(11,108,216,.18),0 64px 120px -24px rgba(11,108,216,.12);
  --shadow-panel:0 24px 64px -24px rgba(11,108,216,.10),inset 0 1px 0 rgba(255,255,255,.88);
  --shadow-glass:0 16px 36px -14px rgba(11,108,216,.16),0 1px 2px rgba(42,33,23,.04);
  --shadow-chip:0 1px 2px rgba(42,33,23,.04),0 8px 20px -14px rgba(11,108,216,.14);
  --shadow-btn:0 12px 26px -10px rgba(11,108,216,.42);
  --drop-1:0 18px 28px rgba(11,108,216,.12);
  --drop-2:0 2px 3px rgba(42,33,23,.08);
  --r-win:32px;
  --r-mobile:24px;
  --r-panel:20px;
  --r-card:18px;
  --r-medium:16px;
  --r-small:10px;
  --r-tiny:8px;
  --r-logo:9px;
  --r-pay:7px;
  --r-pill:999px;
  --r-circle:50%;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --gutter:24px;
  --content-width:1200px;
  --header-height:64px;
  --toc-height:64px;
  --anchor-offset:148px;
  --text-base:16px;
  --display-size:clamp(52px,5vw,68px);
  --h2-size:clamp(28px,3vw,40px);
  --h3-size:22px;
  --section-space:80px;
  --ease-out:cubic-bezier(.22,.61,.36,1);
  --reveal-time:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:80px}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--text-base);line-height:1.6;-webkit-font-smoothing:antialiased}
html.nav-open{overflow:hidden}
[hidden]{display:none!important}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
a{color:var(--accent);text-underline-offset:4px}
a,button,summary{touch-action:manipulation}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--accent);outline-offset:4px}
figure{margin:0}
h1,h2,h3{font-family:var(--font-display);color:var(--text);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:var(--display-size);font-weight:900;line-height:1.1;letter-spacing:-.02em;margin:0 0 24px}
h2{font-size:var(--h2-size);font-weight:800;line-height:1.2;letter-spacing:-.02em;margin:0 0 24px}
h3{font-size:var(--h3-size);line-height:1.35;margin:0 0 16px}
p{margin:0 0 20px}
ul,ol{padding-left:24px}
li+li{margin-top:6px}
code{font-family:var(--font-mono);overflow-wrap:anywhere;font-size:.9em}
pre{max-width:100%;overflow-x:auto;padding:24px;border-radius:var(--r-panel);background:var(--bg-panel-2)}
pre code{overflow-wrap:normal;white-space:pre}
table{border-collapse:collapse}
.no-break{white-space:nowrap}
.wrap{width:100%;max-width:var(--content-width);margin-inline:auto;padding-inline:var(--gutter)}
.section{padding-top:var(--section-space);padding-bottom:var(--section-space)}
.section-head{max-width:760px;margin-bottom:32px}
.muted{color:var(--text-muted)}
.mono{font-family:var(--font-mono)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.icon{width:20px;height:20px;display:inline-block;vertical-align:middle;fill:currentColor}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid>*,.wrap>*,.panel>*,.card>*{min-width:0}
.panel,.card{min-width:0;background:var(--bg-panel);border:1px solid var(--border);box-shadow:var(--shadow-panel)}
.panel{padding:32px;border-radius:var(--r-win)}
.card{padding:24px;border-radius:var(--r-panel)}
.badge{display:inline-flex;align-items:center;gap:6px;max-width:100%;padding:5px 12px;border-radius:var(--r-pill);background:var(--bg-panel-2);color:var(--text-muted);font-size:13px;line-height:1.4;overflow-wrap:anywhere}
.badge-dot{width:7px;height:7px;flex-shrink:0;border-radius:var(--r-circle);background:var(--text-muted)}
.btn,.pill{display:inline-flex;align-items:center;justify-content:center;gap:9px;flex-shrink:0;border:0;border-radius:var(--r-pill);font-weight:700;text-decoration:none;white-space:nowrap;line-height:1.3}
.btn{min-height:52px;padding:14px 30px;font-size:16px}
.pill{min-height:40px;padding:10px 20px;font-size:14.5px}
.btn svg,.pill svg{width:18px;height:18px}
.btn-primary,.pill-primary{color:var(--white);background:linear-gradient(180deg,var(--accent-light),var(--accent));box-shadow:inset 0 1px 0 var(--hi-on-blue),var(--shadow-btn)}
.btn-primary:hover,.pill-primary:hover{background:linear-gradient(180deg,var(--accent),var(--accent-dark))}
.btn-primary:active,.pill-primary:active{background:var(--accent-dark)}
.btn-soft,.pill-soft{background:var(--accent-soft);color:var(--text)}
.btn-soft:hover,.pill-soft:hover{background:var(--accent-soft-2)}
.btn-soft{padding-inline:22px 26px}
.btn-outline{background:var(--bg-panel);border:1px solid var(--border);color:var(--text)}
.btn-outline:hover{border-color:var(--accent);color:var(--accent)}
.btn:disabled,.btn[aria-disabled="true"]{cursor:not-allowed;opacity:.5}
.cta-row{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:14px;margin-bottom:20px}
.topbar{position:relative;z-index:100}
.topbar-in{max-width:1360px;height:var(--header-height);margin:0 auto;padding:0 40px;display:flex;align-items:center;gap:32px;flex-wrap:nowrap}
.brand{display:flex;align-items:center;gap:10px;flex:none;text-decoration:none;color:var(--text);font-family:var(--font-display);font-weight:800;font-size:19px;letter-spacing:-.01em;min-height:40px;white-space:nowrap}
.brand-mark{width:32px;height:32px;border-radius:var(--r-logo);flex:none}
.brand-zh{font-size:15px;font-weight:500;color:var(--text-muted)}
.nav{flex:1;display:flex;justify-content:center;min-width:0}
.nav ul{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:0}
.nav li{display:flex;align-items:center;margin:0}
.nav li+li::before{content:"·";color:var(--text-faint);margin:0 11px;font-weight:700}
.nav a{display:inline-flex;align-items:center;min-height:32px;font-size:14.5px;font-weight:500;color:var(--text-muted);text-decoration:none;white-space:nowrap}
.nav a:hover{color:var(--text)}
.nav a[aria-current="page"]{color:var(--text);font-weight:700}
.nav-end{display:flex;align-items:center;gap:10px;flex-shrink:0}
.lang-picker{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;background:transparent;border-radius:var(--r-pill);font-size:14px;color:var(--text-muted);cursor:pointer;list-style:none}
.lang::-webkit-details-marker{display:none}
.lang span{white-space:nowrap}
.lang svg{width:16px;height:16px;flex:none}
.lang:hover{color:var(--text)}
.lang-panel{position:absolute;right:0;top:calc(100% + 8px);z-index:120;width:180px;padding:8px;background:var(--bg-panel);border:1px solid var(--border);border-radius:var(--r-medium);box-shadow:var(--shadow-glass)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:8px 12px;color:var(--text);text-decoration:none;border-radius:var(--r-small)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--accent-soft)}
.menu-btn{display:none;min-width:44px;min-height:44px;border:0;border-radius:var(--r-pill);background:var(--bg-panel);box-shadow:var(--shadow-chip);align-items:center;justify-content:center;cursor:pointer}
.menu-btn svg{width:20px;height:20px;stroke:currentColor;fill:none;stroke-width:2}
.mobile-drawer{position:fixed;top:var(--header-height);left:0;right:0;z-index:95;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--bg-panel);padding:20px var(--gutter) 40px}
.mobile-drawer a{display:flex;align-items:center;width:100%;min-height:48px;padding:12px 16px;color:var(--text);text-decoration:none;border-radius:var(--r-small)}
.mobile-drawer a:hover,.mobile-drawer a[aria-current="page"]{background:var(--accent-soft)}
.drawer-languages{margin-top:20px;padding-top:16px;border-top:1px solid var(--border)}
.menu-veil{position:fixed;inset:var(--header-height) 0 0;z-index:90;background:var(--veil);border:0;width:100%}
.site-footer{position:relative;z-index:1;border-top:1px solid var(--border);padding-top:56px;padding-bottom:32px;background:var(--bg-panel-2)}
.footer-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr;gap:48px}
.footer-grid>*{min-width:0}
.footer-brand p{max-width:360px;margin-top:20px;color:var(--text-muted)}
.footer-heading{font-size:15px;font-weight:700;margin:0 0 16px}
.footer-links{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 16px}
.footer-links li{margin:0}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px;color:var(--text-muted);text-decoration:none;overflow-wrap:anywhere}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent)}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:32px;padding-top:24px;border-top:1px solid var(--border)}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap;gap:12px;margin-top:20px;color:var(--text-muted);font-size:13px}
.footer-legal{display:flex;gap:20px;flex-wrap:wrap}
.reveal{transition:opacity var(--reveal-time) var(--ease-out),transform var(--reveal-time) var(--ease-out)}
.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:160px;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status+*{margin-top:24px}
#server-status>*{min-width:0;max-width:100%}
.paper{position:relative;overflow-x:clip;max-width:100%;background:radial-gradient(70% 38% at 50% 0,var(--hero-top),transparent 72%),linear-gradient(180deg,var(--hero-top) 0,var(--hero-bottom) 860px,var(--bg) 1180px)}
.paper::before{content:"";position:absolute;inset:0;z-index:0;pointer-events:none;background:var(--text);opacity:.03;-webkit-mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='g'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23g)'/%3E%3C/svg%3E") 0 0/180px 180px repeat;mask:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180'%3E%3Cfilter id='g'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23g)'/%3E%3C/svg%3E") 0 0/180px 180px repeat}
.paper>main,.paper>.site-footer{position:relative;z-index:1}
@media(min-width:1101px) and (max-width:1300px){
  .topbar-in{padding-inline:24px;gap:18px}
  .nav li+li::before{margin-inline:7px}
  .nav a{font-size:13px}
  .nav-end{gap:6px}
  .nav-end .pill{padding-inline:15px}
}
@media(max-width:1100px){
  .topbar-in{padding-inline:var(--gutter);gap:16px}
  .nav{display:none}
  .nav-end{margin-left:auto}
  .menu-btn{display:inline-flex}
  .header-trial{display:none}
  .footer-grid{gap:24px}
}
@media(min-width:1101px){.mobile-drawer,.menu-veil{display:none!important}}
@media(max-width:768px){
  :root{--display-size:40px;--section-space:56px}
  h1{font-size:var(--display-size)}
  .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:640px){
  :root{--gutter:16px;--display-size:36px}
  .no-break{white-space:normal}
  .wrap{padding-inline:var(--gutter)}
  .grid,.footer-grid{grid-template-columns:minmax(0,1fr)}
  .panel{padding:24px;border-radius:var(--r-mobile)}
  .card{padding:20px}
  .topbar-in{gap:8px}
  .brand{gap:7px;font-size:17px}
  .brand-mark{width:28px;height:28px}
  .nav-end{gap:4px;margin-left:auto}
  .nav-end .pill{padding-inline:14px;font-size:13px}
  .lang{padding-inline:6px;font-size:12px}
  .footer-links{gap:8px 16px}
  .tilt,.decor-tilt,[data-tilt]{transform:none}
  .decoration,.stripe-halo{max-width:100%}
  .footer-bottom{align-items:flex-start;flex-direction:column}
}
@media(max-width:400px){
  .nav-end .lang span{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}
  .nav-end .lang{padding:0;min-height:44px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending,.reveal.shown{opacity:1;transform:none;transition:none}
}