:root {
  --bg:#E2F0F3;
  --bg-top:#EEF7F9;
  --bg-bottom:#DCEBEF;
  --panel:#F6FBFC;
  --panel-2:#D4E7EC;
  --border:#C3DBE2;
  --border-soft:#DCEBEF;
  --surface:#FFFFFF;
  --accent:#E9683B;
  --accent-soft:#EF7D52;
  --accent-dark:#B9461F;
  --text:#1C2A31;
  --muted:#566A74;
  --ink-teal:#2C6575;
  --success:#2F9E6A;
  --indigo:#4C5FD5;
  --warn:#C08512;
  --error:#CF3F3A;
  --apricot:#F8E6D6;
  --apricot-edge:#EDCDB2;
  --indigo-panel:#E5E8F7;
  --doodle-apricot:#DE9E70;
  --doodle-ice:#5FA3B6;
  --flag-red:#D52B3A;
  --flag-white:#FFFFFF;
  --flag-blue:#2A4B97;
  --flag-navy:#1E2C69;
  --hi:rgb(255 255 255 / .9);
  --transparent:transparent;
  --ink-rgb:23 62 74;
  --accent-rgb:233 104 59;
  --success-rgb:47 158 106;
  --indigo-rgb:76 95 213;
  --white-rgb:255 255 255;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans GB","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;
  --weight-normal:400;
  --weight-medium:500;
  --weight-semibold:600;
  --weight-bold:700;
  --weight-brand:800;
  --size-body:15px;
  --size-small:13px;
  --size-caption:12px;
  --size-micro:11.5px;
  --size-nav:15px;
  --size-brand:20px;
  --size-button:16px;
  --size-login:14.5px;
  --size-label:14px;
  --size-row:13.5px;
  --size-chip:12.5px;
  --size-lead:20px;
  --size-doc:24px;
  --size-h1:clamp(52px,5.34vw,64px);
  --size-h2:clamp(28px,3vw,36px);
  --size-h3:24px;
  --r-window:24px;
  --r-feature:28px;
  --r-card:16px;
  --r-row:10px;
  --r-side:9px;
  --r-tab:12px;
  --r-pill:999px;
  --r-round:50%;
  --gutter:24px;
  --width-wrap:1200px;
  --width-reading:820px;
  --header-height:64px;
  --anchor-offset:80px;
  --toc-offset:88px;
  --toc-anchor-offset:160px;
  --shadow-window:0 1px 2px rgb(var(--ink-rgb) / .06),0 24px 60px -10px rgb(var(--ink-rgb) / .10),0 56px 110px -30px rgb(var(--ink-rgb) / .10);
  --shadow-accent:0 2px 4px rgb(var(--accent-rgb) / .06),0 16px 40px -6px rgb(var(--accent-rgb) / .12);
  --shadow-soft:0 1px 2px rgb(var(--ink-rgb) / .05),0 8px 22px -8px rgb(var(--ink-rgb) / .10);
  --shadow-button:inset 0 1px 0 rgb(var(--white-rgb) / .22),0 12px 26px -10px rgb(var(--accent-rgb) / .55);
  --ease-arrival:cubic-bezier(.2,.7,.2,1);
  --duration-ui:.2s;
  --duration-reveal:.5s;
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-padding-top:var(--anchor-offset);scroll-behavior:smooth}
html.nav-open{overflow:hidden}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--size-body);font-weight:var(--weight-normal);line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
img{display:block;max-width:100%;height:auto}
svg{flex-shrink:0}
[hidden]{display:none!important}
:where(a,button,summary,input,select,textarea,[tabindex]):focus-visible{outline:2px solid var(--ink-teal);outline-offset:3px}
h1,h2,h3{font-family:var(--font-display);font-weight:var(--weight-bold);text-wrap:balance;overflow-wrap:break-word}
h1{font-size:var(--size-h1);line-height:1.12;letter-spacing:-.02em}
h2{font-size:var(--size-h2);line-height:1.2;letter-spacing:-.02em}
h3{font-size:var(--size-h3);line-height:1.3}
p{margin:0 0 1em}
code{font-family:var(--font-mono);font-size:.9em;overflow-wrap:anywhere}
pre{max-width:100%;overflow-x:auto;padding:20px;background:var(--panel-2);border-radius:var(--r-card)}
pre code{overflow-wrap:normal;white-space:pre}
table{border-collapse:collapse}
th,td{word-break:keep-all}
.wrap{max-width:var(--width-wrap);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.reading-wrap{max-width:var(--width-reading);margin-inline:auto;padding-inline:var(--gutter);min-width:0}
.section{padding-top:64px;padding-bottom:64px}
.section-head{margin-bottom:28px}
.section-head h2{margin:0 0 12px}
.section-head p{color:var(--muted);max-width:var(--width-reading)}
.prose{min-width:0;overflow-wrap:break-word}
.prose :where(h2,h3){margin-top:1.8em;margin-bottom:.65em}
.prose p,.prose li{line-height:1.85}
.prose a{color:var(--indigo);text-decoration:underline;text-underline-offset:3px}
.prose section[id]{scroll-margin-top:var(--anchor-offset)}
.muted{color:var(--muted)}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.no-break{white-space:nowrap}
.panel,.card{min-width:0;padding:24px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-card);box-shadow:inset 0 1px 0 var(--hi),var(--shadow-soft)}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:24px}
.grid>*{min-width:0}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:50px;padding:0 30px;border-radius:var(--r-pill);font-size:var(--size-button);font-weight:var(--weight-semibold);text-align:center;border:0;flex-shrink:0;white-space:nowrap;transition:transform var(--duration-ui),background-color var(--duration-ui),box-shadow var(--duration-ui)}
.btn-main,.btn-primary{color:var(--surface);background:linear-gradient(180deg,var(--accent-soft),var(--accent));box-shadow:var(--shadow-button)}
.btn-main:hover,.btn-primary:hover{background:var(--accent-dark);transform:translateY(-1px)}
.btn-main:active,.btn-primary:active{transform:translateY(1px)}
.btn-line,.btn-secondary{color:var(--text);border:1.5px solid var(--text);background:var(--transparent)}
.btn-line:hover,.btn-secondary:hover{background:var(--surface)}
.btn:disabled,.btn[aria-disabled="true"]{opacity:.55;pointer-events:none}
.button-row{display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.reveal{transition:opacity var(--duration-reveal),transform var(--duration-reveal) var(--ease-arrival)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
#server-status{position:static;display:block;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}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.ico{fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}

/* Shared navigation */
.topbar,#site-header{position:relative;z-index:30}
.topbar-in{height:var(--header-height);display:flex;align-items:center;gap:36px;position:relative}
.brand{display:inline-flex;align-items:center;gap:10px;flex-shrink:0}
.brand-mark{width:28px;height:28px;flex-shrink:0}
.brand-word{font-family:var(--font-display);font-weight:var(--weight-brand);font-size:var(--size-brand);letter-spacing:-.02em}
.nav-list{display:flex;align-items:center;gap:2px;list-style:none;margin:0;padding:0}
.nav-link{display:inline-flex;align-items:center;gap:6px;min-height:36px;padding:0 14px;border-radius:var(--r-pill);font-size:var(--size-nav);color:var(--text);background:var(--transparent);border:0;cursor:pointer;transition:background-color var(--duration-ui)}
.nav-link:hover,.nav-link:focus-visible{background:rgb(var(--ink-rgb) / .06)}
.nav-link[aria-current="page"]{background:rgb(var(--ink-rgb) / .07);font-weight:var(--weight-semibold)}
.nav-link svg{width:12px;height:12px}
.more{position:relative}
.menu{position:absolute;left:-8px;top:100%;padding-top:10px;display:none}
.more.is-open .menu,.more[open] .menu{display:block}
.more>summary{list-style:none}
.more>summary::-webkit-details-marker{display:none}
.menu-panel{width:260px;padding:10px;border-radius:var(--r-card);background:var(--surface);border:1px solid var(--border);box-shadow:var(--shadow-window)}
.menu-group{margin:6px 10px 4px;font-size:var(--size-micro);letter-spacing:.06em;color:var(--muted)}
.menu-panel a{display:flex;flex-direction:column;padding:8px 10px;border-radius:var(--r-row);min-height:44px}
.menu-panel a:hover,.menu-panel a:focus-visible,.menu-panel a[aria-current="page"]{background:var(--panel)}
.menu-panel span{font-size:var(--size-label);font-weight:var(--weight-semibold)}
.menu-panel small{font-size:var(--size-caption);color:var(--muted);line-height:1.5}
.nav-end{margin-left:auto;display:flex;align-items:center;gap:10px}
.lang-box{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:38px;min-width:44px;width:auto;padding:0 14px;border-radius:var(--r-pill);border:0;background:var(--transparent);font-size:var(--size-label);color:var(--muted);cursor:pointer;list-style:none}
.lang span{white-space:nowrap}
.lang::-webkit-details-marker{display:none}
.lang:hover{background:rgb(var(--ink-rgb) / .06)}
.lang svg{width:16px;height:16px}
.language-menu{position:absolute;right:0;top:calc(100% + 8px);width:180px;padding:8px;background:var(--surface);border:1px solid var(--border);border-radius:var(--r-card);box-shadow:var(--shadow-soft)}
.language-menu a{display:flex;align-items:center;min-height:44px;padding:8px 12px;border-radius:var(--r-row)}
.language-menu a:hover,.language-menu a[aria-current="true"]{background:var(--panel-2)}
.login{display:inline-flex;align-items:center;justify-content:center;min-height:40px;padding:0 22px;border-radius:var(--r-pill);background:var(--text);color:var(--surface);font-size:var(--size-login);font-weight:var(--weight-semibold);white-space:nowrap;box-shadow:inset 0 1px 0 rgb(var(--white-rgb) / .12),var(--shadow-soft);transition:transform var(--duration-ui)}
.login:hover{transform:translateY(-1px)}
.nav-toggle{display:none;align-items:center;justify-content:center;min-width:44px;min-height:44px;background:var(--panel);border:1px solid var(--border);border-radius:var(--r-pill)}
.nav-toggle svg{width:20px;height:20px}
.nav-drawer{display:none}
.nav-veil{position:fixed;inset:var(--header-height) 0 0;border:0;background:rgb(var(--ink-rgb) / .2);z-index:31}
.nav-drawer a{display:flex;width:100%;align-items:center;min-height:44px;padding:12px 16px;border-radius:var(--r-row)}
.nav-drawer a:hover,.nav-drawer a[aria-current]{background:var(--panel-2)}
.drawer-label{margin:14px 16px 4px;color:var(--muted);font-size:var(--size-caption)}
.skip-link{position:absolute;left:var(--gutter);top:8px;transform:translateY(-150%);padding:8px 16px;background:var(--surface);border-radius:var(--r-pill);z-index:50}
.skip-link:focus{transform:none}

/* Shared footer */
.site-footer{background:var(--panel-2);border-top:1px solid var(--border);padding-top:48px;padding-bottom:24px}
.footer-grid{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:48px}
.footer-grid>*{min-width:0}
.footer-intro{margin-top:16px;max-width:340px;color:var(--muted)}
.footer-title{font-size:var(--size-label);font-weight:var(--weight-semibold);margin:0 0 14px}
.footer-links{list-style:none;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px 16px;margin:0;padding:0}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:32px}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--indigo);text-decoration:underline}
.footer-languages{display:flex;gap:8px 20px;flex-wrap:wrap;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(--border);font-size:var(--size-small);color:var(--muted)}
.footer-legal{display:flex;gap:20px;flex-wrap:wrap}

/* Approved first-screen shell and copy */
.screen{position:relative;overflow-x:clip;max-width:100%;background:linear-gradient(180deg,var(--bg-top) 0%,var(--bg-bottom) 100%)}
.tex{position:absolute;inset:0;width:100%;height:100%;opacity:.04;pointer-events:none}
.tex path,.tex circle{fill:none;stroke:var(--text);stroke-width:2.2;stroke-linecap:round}
.hero{position:relative;padding-top:28px;padding-bottom:64px}
.hero-copy{position:relative;z-index:6;display:flex;flex-direction:column;align-items:center;text-align:center}
.eyebrow{display:inline-flex;align-items:center;gap:8px;min-height:30px;padding:0 14px;border-radius:var(--r-pill);background:var(--panel);border:1px solid var(--border);font-size:var(--size-small);font-weight:var(--weight-medium);color:var(--muted);box-shadow:inset 0 1px 0 var(--hi)}
.eyebrow-dot{width:7px;height:7px;border-radius:var(--r-round);background:var(--ink-teal);flex-shrink:0}
.h1{margin:18px 0 0;font-family:var(--font-display);font-size:var(--size-h1);line-height:1.08;font-weight:var(--weight-bold);letter-spacing:-.03em;color:var(--text)}
.h1 .line{display:block}
.mark{position:relative;display:inline-block;isolation:isolate}
.ring{position:absolute;left:-8%;top:-12%;width:116%;height:128%;z-index:-1;overflow:visible;pointer-events:none}
.ring-stroke{fill:none;stroke:var(--accent);stroke-opacity:.35;stroke-width:6;stroke-linecap:round;stroke-linejoin:round}
.lead{margin:18px 0 0;max-width:820px;font-size:var(--size-lead);line-height:1.5;color:var(--muted)}
.lead strong{color:var(--text);font-weight:var(--weight-semibold);background:linear-gradient(var(--transparent) 64%,var(--apricot) 64%,var(--apricot) 92%,var(--transparent) 92%)}
.cta-row{margin-top:24px;display:flex;align-items:center;justify-content:center;gap:12px}
.cta-sep{width:1px;height:36px;margin:0 10px;background:var(--border);flex-shrink:0}
.trust{display:flex;align-items:center;gap:18px;list-style:none;margin:0;padding:0;font-size:var(--size-row);color:var(--muted)}
.trust li{display:inline-flex;align-items:center;gap:6px;white-space:nowrap}
.trust svg{width:16px;height:16px;flex-shrink:0;color:var(--ink-teal)}
.platforms{margin-top:20px;display:flex;align-items:center;justify-content:center;gap:22px;list-style:none;padding:0;font-size:var(--size-small);color:var(--muted)}
.platforms li{display:inline-flex;align-items:center;gap:7px}
.platforms svg{width:16px;height:16px;flex-shrink:0;color:var(--text)}
.platforms .pf-label{font-size:var(--size-caption);letter-spacing:.06em;color:var(--muted);padding-right:4px}

@media(max-width:960px){
  .nav{display:none}
  .nav-end{margin-left:auto}
  .nav-toggle{display:inline-flex}
  .nav-drawer:not([hidden]){display:block;position:absolute;z-index:33;top:var(--header-height);left:var(--gutter);right:var(--gutter);max-height:calc(100dvh - var(--header-height) - 16px);overflow-y:auto;overscroll-behavior:contain;padding:12px;background:var(--surface);border:1px solid var(--border);border-radius:var(--r-card);box-shadow:var(--shadow-window)}
  .h1{font-size:52px}
  .cta-row{flex-wrap:wrap}
  .cta-sep{display:none}
  .trust{width:100%;justify-content:center;flex-wrap:wrap;gap:8px 18px}
  .footer-grid{gap:24px}
}
@media(max-width:768px){
  h1{font-size:36px}
  .hero{padding-top:24px;padding-bottom:48px}
  .h1{font-size:36px;line-height:1.15}
  .lead{font-size:17px}
  .trust{display:grid;grid-template-columns:repeat(2,auto);justify-content:center;gap:8px 18px}
  .platforms{flex-wrap:wrap;gap:10px 18px}
  .platforms .pf-label{width:100%;padding:0}
  .lang-text{display:none}
  .grid,.footer-grid{grid-template-columns:1fr}
  .section{padding-top:40px;padding-bottom:40px}
}
@media(max-width:640px){
  :root{--gutter:16px}
  .no-break{white-space:normal}
  .btn{padding:0 24px}
  .topbar-in{gap:12px}
  .nav-end{gap:4px;margin-left:auto}
  .lang{padding:0 8px}
  .login{padding:0 16px}
  .tilt,.note,[data-tilt]{transform:none}
  .screen,.hero{max-width:100%}
  .footer-bottom{align-items:flex-start;flex-direction:column}
}
@media(max-width:420px){
  .trust{grid-template-columns:1fr;justify-items:start}
  .brand{gap:6px}
  .brand-word{font-size:18px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation:none!important;transition:none!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}