:root{
  --c-bg:#F5EEE2;
  --c-bg-top:#FAF5EC;
  --c-bg-bottom:#F1E8D9;
  --c-panel:#FFFBF4;
  --c-groove:#EDE3D3;
  --c-groove-deep:#E4D8C5;
  --c-border:#E0D3BF;
  --c-accent:#0B8F7D;
  --c-accent-dark:#076A5D;
  --c-accent-light:#2FA592;
  --c-accent-mist:#EAF7F3;
  --c-accent-tint:#C9E9E0;
  --c-cobalt:#2F5BD8;
  --c-cobalt-deep:#2448B4;
  --c-text:#2A2016;
  --c-text-muted:#6E6253;
  --c-text-soft:#9A8C79;
  --c-success:#3C8A3F;
  --c-warn:#C9821A;
  --c-error:#C2412D;
  --c-sky:#DCEAF2;
  --c-rose:#F4E0DE;
  --c-apricot:#F6E2C9;
  --c-ink:#221A12;
  --c-ink-2:#2F251B;
  --c-ink-line:rgba(255,251,244,.08);
  --c-term-text:#E9DFCE;
  --c-term-dim:#8F8170;
  --c-term-key:#8FD6C8;
  --c-term-str:#F1E4CF;
  --c-on-ink-dim:rgba(255,251,244,.62);
  --c-flag-ink:#6E6253;
  --c-flag-deep:#4E4337;
  --c-flag-mid:#B3A48F;
  --c-glass-hi:rgba(255,251,244,.74);
  --c-glass-mid:rgba(234,247,243,.34);
  --c-glass-low:rgba(47,91,216,.10);
  --c-glass-edge:rgba(255,251,244,.92);
  --c-glass-inner:rgba(11,143,125,.12);
  --c-hi:rgba(255,251,244,.9);
  --c-grid:rgba(42,32,22,.04);
  --c-glow:rgba(11,143,125,.12);
  --c-contact:rgba(7,106,93,.16);
  --c-shadow-accent:rgba(11,143,125,.10);
  --c-shadow-accent-strong:rgba(11,143,125,.14);
  --c-shadow-ink:rgba(42,32,22,.08);
  --c-shadow-deep:rgba(42,32,22,.32);
  --c-mask:#000;
  --c-clear:transparent;

  --f-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,sans-serif;
  --f-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --f-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,"Liberation Mono",monospace;
  --fs-body:16px;
  --fs-small:14px;
  --fs-caption:12px;
  --fs-label:11.5px;
  --fs-lede:20px;
  --fs-display:66px;
  --fs-h2:40px;
  --fs-h3:24px;
  --fs-stat:72px;
  --weight-normal:400;
  --weight-medium:500;
  --weight-semibold:600;
  --weight-bold:800;
  --r-xs:4px;
  --r-sm:6px;
  --r-md:8px;
  --r-pill:999px;
  --r-circle:50%;
  --sh-card:0 24px 60px -20px var(--c-shadow-accent-strong),0 2px 8px var(--c-shadow-ink),inset 0 0 0 1px var(--c-hi);
  --sh-float:0 18px 40px -14px var(--c-shadow-accent-strong),0 1px 3px var(--c-shadow-ink),inset 0 0 0 1px var(--c-hi);
  --sh-button:0 14px 28px -14px var(--c-shadow-deep);
  --sh-terminal:0 26px 50px -16px var(--c-shadow-deep),inset 0 0 0 1px var(--c-ink-line);
  --wrap:1360px;
  --gutter:40px;
  --space-section:80px;
  --anchor-offset:96px;
  --toc-offset:16px;
  --toc-landing:88px;
  --ease:200ms ease;
}
*,*::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-text);font-family:var(--f-body);font-size:var(--fs-body);line-height:1.6;-webkit-font-smoothing:antialiased}
html.nav-open{overflow:hidden}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button,a,summary{touch-action:manipulation}
button{color:inherit}
img,svg{vertical-align:middle}
img{max-width:100%;height:auto}
svg{flex-shrink:0}
[hidden]{display:none!important}
:focus-visible{outline:2px solid var(--c-accent);outline-offset:3px;border-radius:var(--r-xs)}
ul,ol{margin:0;padding:0;list-style:none}
h1,h2,h3,h4,p{margin-top:0}
h1,h2,h3{font-family:var(--f-display);text-wrap:balance}
h1{font-size:clamp(52px,4.6vw,72px);font-weight:var(--weight-bold);line-height:1.1;letter-spacing:-.02em}
h2{font-size:var(--fs-h2);font-weight:var(--weight-bold);line-height:1.15;letter-spacing:-.02em}
h3{font-size:var(--fs-h3);line-height:1.35;font-weight:var(--weight-semibold)}
p{margin-bottom:1.25em}
code{font-family:var(--f-mono);overflow-wrap:anywhere}
pre{max-width:100%;min-width:0;overflow-x:auto;padding:20px;background:var(--c-ink);color:var(--c-term-text);border-radius:var(--r-sm)}
pre code{overflow-wrap:normal;white-space:pre}
table{border-collapse:collapse}
th,td{word-break:keep-all}
.wrap{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:var(--gutter)}
.wrap>*{min-width:0}
.section{padding-top:var(--space-section);padding-bottom:var(--space-section)}
.reading-wrap{max-width:880px}
.mono{font-family:var(--f-mono);text-transform:uppercase;letter-spacing:.08em}
.no-break{white-space:nowrap}
.muted{color:var(--c-text-muted)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.panel,.card{min-width:0;background:var(--c-panel);border-radius:var(--r-md);box-shadow:var(--sh-card);padding:28px}
.groove{background:var(--c-groove)}
.card-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.prose{min-width:0;overflow-wrap:break-word}
.prose h2{margin-top:56px}
.prose h3{margin-top:32px}
.prose ul,.prose ol{padding-left:1.5em;list-style:revert}
.prose li{margin-bottom:8px}
.prose a:not(.btn){color:var(--c-accent-dark);text-decoration:underline;text-underline-offset:4px}
.prose code:not(pre code){background:var(--c-groove);padding:2px 5px;border-radius:var(--r-xs)}
.btn{display:inline-flex;align-items:center;justify-content:center;flex-shrink:0;gap:12px;min-height:54px;padding:12px 22px;border:0;border-radius:var(--r-sm);font-size:var(--fs-body);font-weight:var(--weight-semibold);white-space:nowrap;transition:transform var(--ease),background var(--ease),box-shadow var(--ease)}
.btn .mono{font-size:11px;font-weight:var(--weight-medium)}
.btn-solid,.btn-primary{background:var(--c-text);color:var(--c-panel);box-shadow:var(--sh-button)}
.btn-solid .mono,.btn-primary .mono{color:var(--c-on-ink-dim)}
.btn-solid:hover,.btn-primary:hover,.btn.is-hover{background:var(--c-accent-dark);transform:translateY(-1px)}
.btn-soft,.btn-secondary{background:var(--c-groove);color:var(--c-text);box-shadow:inset 0 0 0 1px var(--c-border)}
.btn-soft .mono{color:var(--c-text-muted)}
.btn-soft:hover,.btn-secondary:hover{background:var(--c-groove-deep);transform:translateY(-1px)}
.btn:active,.btn.is-active{transform:translateY(1px)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--c-groove);color:var(--c-text-muted);box-shadow:none;cursor:not-allowed;transform:none}
.btn-small{min-height:44px;font-size:var(--fs-small);padding:10px 16px}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin-top:36px}
.topbar{position:relative;z-index:30;padding-top:16px}
.topbar-card{position:relative;display:flex;align-items:center;justify-content:space-between;gap:20px;min-height:64px;padding:0 12px 0 20px;background:var(--c-panel);border-radius:var(--r-md);box-shadow:var(--sh-card)}
.topbar>.topbar-card{width:calc(100% - 80px);max-width:1280px}
.brandmark{display:inline-flex;align-items:center;gap:10px;flex-shrink:0;min-height:44px}
.brandmark img{display:block;width:34px;height:34px;flex-shrink:0}
.brandmark-en{font-family:var(--f-display);font-weight:var(--weight-bold);font-size:19px;letter-spacing:-.02em}
.brandmark-zh{font-size:13px;color:var(--c-text-muted);font-weight:var(--weight-medium)}
.tabs ul{display:flex;align-items:center;list-style:none;margin:0;padding:0}
.tabs a{position:relative;display:flex;align-items:center;height:64px;padding:0 13px;font-size:15px;font-weight:var(--weight-medium);color:var(--c-text-muted);white-space:nowrap;transition:color var(--ease)}
.tabs a:hover{color:var(--c-text)}
.tabs a::after{content:"";position:absolute;left:13px;right:13px;bottom:0;height:3px;border-radius:var(--r-xs);background:var(--c-accent);transform:scaleX(0);transition:transform var(--ease)}
.tabs a:hover::after{transform:scaleX(.35)}
.tabs a[aria-current="page"]{color:var(--c-text);font-weight:var(--weight-semibold)}
.tabs a[aria-current="page"]::after{transform:scaleX(1)}
.topbar-tools{display:flex;align-items:center;gap:8px;flex-shrink:0;margin-left:auto}
.lang-area{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:44px;min-width:44px;width:auto;padding:0 10px;border:0;background:var(--c-clear);color:var(--c-text-muted);font-size:var(--fs-small);border-radius:var(--r-sm)}
.lang span{white-space:nowrap}
.lang:hover{background:var(--c-groove);color:var(--c-text)}
.language-menu{position:absolute;right:0;top:calc(100% + 8px);width:180px;padding:8px;background:var(--c-panel);border:1px solid var(--c-border);border-radius:var(--r-md);box-shadow:var(--sh-card);z-index:40}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-xs)}
.language-menu a:hover,.language-menu a[aria-current="true"]{background:var(--c-accent-tint)}
.login{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:40px;padding:8px 16px;border-radius:var(--r-sm);background:var(--c-panel);border:1px solid var(--c-text);font-size:var(--fs-small);font-weight:var(--weight-semibold);white-space:nowrap;transition:background var(--ease),color var(--ease)}
.login .mono{font-size:10.5px;color:var(--c-text-muted)}
.login:hover{background:var(--c-text);color:var(--c-panel)}
.login:hover .mono{color:var(--c-on-ink-dim)}
.menu-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;border:1px solid var(--c-border);border-radius:var(--r-sm);background:var(--c-groove);font-size:var(--fs-lede)}
.nav-drawer{display:none}
.nav-veil{position:fixed;inset:0;z-index:20;background:var(--c-shadow-deep);border:0}
.site-footer{background:var(--c-groove);border-top:1px solid var(--c-border);padding-top:56px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.25fr 1fr 1fr;gap:48px}
.footer-brand p{margin-top:16px;max-width:350px;color:var(--c-text-muted)}
.footer-heading{font-family:var(--f-mono);font-size:var(--fs-caption);letter-spacing:.08em;margin-bottom:16px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px 16px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px;font-size:var(--fs-small)}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--c-accent-dark);text-decoration:underline;text-underline-offset:4px}
.footer-languages{display:flex;flex-wrap:wrap;gap:8px 20px;margin-top:32px}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-top:24px;padding-top:20px;border-top:1px solid var(--c-border);font-size:var(--fs-small);color:var(--c-text-muted)}
.footer-legal{display:flex;flex-wrap:wrap;gap:20px}
.reveal{transition:opacity 600ms ease,transform 600ms ease}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:relative;display:block;min-height:64px;min-width:0;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status>*{min-width:0;max-width:100%}
#server-status+*{margin-top:24px}
.decoration-zone,.stripe-halo-zone{position:relative;overflow-x:clip;max-width:100%}
@media(max-width:1200px){
  .tabs a{padding-inline:10px;font-size:var(--fs-small)}
  .tabs a::after{left:10px;right:10px}
  .topbar-card{gap:12px}
  .brandmark-zh{display:none}
}
@media(max-width:1100px){
  .topbar-card>.tabs{display:none}
  .menu-toggle{display:inline-flex}
  .topbar-tools{margin-left:auto}
  .nav-drawer{position:absolute;top:calc(100% + 8px);left:0;right:0;z-index:35;display:block;background:var(--c-panel);border:1px solid var(--c-border);border-radius:var(--r-md);box-shadow:var(--sh-card);padding:8px 16px;max-height:calc(100dvh - 100px);overflow-y:auto;overscroll-behavior:contain}
  .nav-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:10px 12px;color:var(--c-text)}
  .nav-drawer a:hover,.nav-drawer a[aria-current]{background:var(--c-accent-tint);border-radius:var(--r-xs)}
  .drawer-languages{border-top:1px solid var(--c-border);padding-top:8px;margin-top:8px}
}
@media(max-width:768px){
  :root{--gutter:16px;--space-section:48px;--fs-h2:30px}
  h1{font-size:40px;line-height:1.12}
  .card-grid{grid-template-columns:1fr}
  .topbar>.topbar-card{width:calc(100% - 32px)}
  .footer-grid{grid-template-columns:1fr;gap:28px}
  .panel,.card{padding:20px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,.tilt-content{transform:none}
  .decoration-zone,.stripe-halo-zone{max-width:100%}
  .topbar-card{padding-inline:10px;gap:8px}
  .topbar-tools{margin-left:auto;gap:4px}
  .brandmark{gap:6px}
  .brandmark-en{font-size:var(--fs-body)}
  .brandmark img{width:28px;height:28px}
  .lang{padding-inline:6px}
  .lang .lang-name{display:none}
  .login{padding-inline:10px}
  .login .mono{display:none}
  h1{font-size:38px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  .reveal,.reveal.pending{opacity:1;transform:none;transition:none}
  *,*::before,*::after{animation-duration:0s!important;transition-duration:0s!important}
}