/* BidCore site foundation — 2026-09-27
 * Paper, ink and one serif: the same tokens as the desktop app (src/styles/tokens.css).
 * Headings use a self-hosted subset of Source Han Serif CN (SIL OFL 1.1).
 */
@font-face{font-family:"BC Serif";src:url("../assets/fonts/bc-serif-400.woff2?v=20260927") format("woff2");font-weight:400;font-style:normal;font-display:swap}

:root{
  color-scheme:light;
  --paper:#f7f6f3;--paper-2:#efede7;--surface:#fff;--glass:rgba(255,255,255,.86);
  --ink:#171713;--ink-2:#46463f;--muted:#6f6f68;--faint:#9d9d95;
  --line:rgba(23,23,19,.08);--line-2:rgba(23,23,19,.14);
  --accent:#3b82f6;--ok:#3d8a4f;--warn:#c48a1c;
  --serif:"BC Serif","Source Han Serif SC","Source Han Serif CN","Noto Serif SC","Songti SC",STSong,serif;
  --sans:"PingFang SC","HarmonyOS Sans SC","Microsoft YaHei","Source Han Sans SC",-apple-system,BlinkMacSystemFont,system-ui,sans-serif;
  --ease:cubic-bezier(.2,.8,.2,1);
  --shadow-float:0 8px 28px rgba(23,23,19,.08),0 1px 2px rgba(23,23,19,.04);
  --shadow-lift:0 30px 80px rgba(20,24,30,.18),0 2px 8px rgba(20,24,30,.08);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:96px;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--paper);color:var(--ink);font:15px/1.75 var(--sans);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a{color:inherit;text-decoration:none}
img,video{display:block;max-width:100%;height:auto}
/* centered lines: trailing punctuation hangs past the line end, so the words alone sit on the center line */
h1,h2,h3{text-wrap:balance}p,li{text-wrap:pretty}
.hang{letter-spacing:0;margin-inline-end:-1em}
@media (max-width:720px){.hang-m{letter-spacing:0;margin-inline-end:-1em}}

button{font:inherit;color:inherit;cursor:pointer}
button,a,summary{-webkit-tap-highlight-color:transparent}
:where(a,button,summary,[tabindex]):focus-visible{outline:2px solid color-mix(in srgb,var(--accent) 70%,transparent);outline-offset:4px;border-radius:6px}
h1,h2,h3,p{margin:0}
h1,h2,h3{font-family:var(--serif);font-weight:400;letter-spacing:-.02em}
h1{font-size:clamp(40px,6vw,88px);line-height:1.22}
h2{font-size:clamp(min(34px,calc((100vw - 48px) / 9)),4.2vw,60px);line-height:1.28}
h3{font-size:24px;line-height:1.45}
.serif{font-family:var(--serif);font-weight:400}
.eyebrow{font-size:13px;letter-spacing:.14em;color:var(--muted)}
.skip{position:fixed;top:-100px;left:16px;z-index:60;background:var(--surface);padding:10px 14px;border-radius:10px}
.skip:focus{top:12px}
[hidden]{display:none!important}

/* ── buttons ── */
.button{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:48px;padding:0 28px;border:0;border-radius:999px;background:var(--ink);color:#fff;font-size:15px;font-weight:500;letter-spacing:.02em;transition:transform .25s var(--ease),background .25s}
.button:hover{background:#34342d;transform:translateY(-2px)}
.button.secondary,.button.ghost{background:rgba(255,255,255,.7);color:var(--ink);box-shadow:inset 0 0 0 1px var(--line-2)}
.button.secondary:hover,.button.ghost:hover{background:var(--surface)}
.button .play{width:18px;height:18px;border-radius:50%;background:var(--ink);color:#fff;display:inline-grid;place-items:center;font-size:8px;padding-left:1px}
.text-link{display:inline-flex;align-items:center;gap:6px;border-bottom:1px solid var(--line-2);padding-bottom:3px;transition:border-color .25s}
.text-link:hover{border-color:var(--ink)}

/* ── header: full-width bar at the top, floating pill once the page scrolls ── */
.header{position:sticky;top:0;z-index:40;display:flex;align-items:center;justify-content:space-between;gap:28px;height:76px;padding:0 max(5.5%,calc((100% - 1600px) / 2 + 5.5%));transition:padding .45s var(--ease)}
.header::before{content:"";position:absolute;inset:10px auto 10px 50%;width:100%;max-width:100%;transform:translateX(-50%);border-radius:999px;background:transparent;box-shadow:none;transition:width .45s var(--ease),background .35s,box-shadow .35s,top .45s;z-index:-1}
.header.is-scrolled::before{width:min(980px,calc(100% - 32px));background:var(--glass);backdrop-filter:blur(18px) saturate(1.2);-webkit-backdrop-filter:blur(18px) saturate(1.2);box-shadow:var(--shadow-float),inset 0 0 0 1px var(--line)}
.header.is-scrolled{padding:0 max(36px,calc((100% - 980px) / 2 + 20px))}
.brand{display:flex;align-items:center;gap:11px;flex-shrink:0}
.brand img{width:34px;height:34px}
.brand span{font:400 30px/1 var(--serif);letter-spacing:-.02em}
.header.is-scrolled .brand span{font-size:26px}
.header nav{display:flex;gap:44px;font-size:14.5px;white-space:nowrap}
.header nav a{position:relative;color:var(--ink-2);transition:color .2s}
.header nav a:hover,.header nav a[aria-current=page]{color:var(--ink)}
.header nav a::after{content:"";position:absolute;left:0;right:0;bottom:-4px;height:1px;background:currentColor;transform:scaleX(0);transform-origin:left;transition:transform .3s var(--ease)}
.header nav a:hover::after,.header nav a[aria-current=page]::after{transform:scaleX(1)}
.nav-cta{min-height:40px;padding:0 20px;font-size:14px;white-space:nowrap;flex-shrink:0}

/* ── footer ── */
footer{max-width:1600px;margin:0 auto;padding:44px 5.5% 40px;display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:24px 40px;border-top:1px solid var(--line)}
footer .brand span{font-size:26px}
footer p{font-size:13px;color:var(--muted)}
footer nav{display:flex;gap:24px;font-size:13px;color:var(--muted)}
footer nav a:hover{color:var(--ink)}
.maker{grid-column:1/-1;display:flex;align-items:center;justify-content:space-between;gap:18px;padding-top:22px;border-top:1px solid var(--line);font-size:12px;color:var(--faint)}
.maker .by{display:inline-flex;align-items:center;gap:10px;color:var(--muted)}
.maker .by img{width:22px;height:22px}
.maker a:hover{color:var(--ink)}

/* ── reveal on scroll ── */
.motion .reveal{opacity:0;transform:translateY(26px);transition:opacity .9s var(--ease),transform .9s var(--ease);transition-delay:var(--d,0ms)}
.motion .reveal.in{opacity:1;transform:none}

/* ── image dialog ── */
dialog.zoom{width:min(1480px,94vw);max-height:94vh;border:0;padding:52px 16px 16px;border-radius:22px;background:var(--paper)}
dialog.zoom::backdrop{background:rgba(21,27,35,.72);backdrop-filter:blur(4px)}
dialog.zoom img{max-height:82vh;width:auto;margin:auto;border-radius:10px;object-fit:contain}
dialog.zoom .close{position:absolute;right:16px;top:12px;border:0;border-radius:999px;background:var(--surface);box-shadow:inset 0 0 0 1px var(--line-2);padding:4px 16px;font-size:13px}
dialog[open]{animation:dlg .3s var(--ease)}
@keyframes dlg{from{opacity:0;transform:translateY(10px) scale(.985)}to{opacity:1;transform:none}}

/* ── consent banner (js/site.js) ── */
.bc-consent{position:fixed;left:20px;bottom:20px;z-index:50;max-width:380px;padding:16px 18px;border-radius:18px;background:var(--surface);box-shadow:var(--shadow-float),inset 0 0 0 1px var(--line);font-size:13px;line-height:1.7;color:var(--ink-2)}
.bc-consent a{text-decoration:underline;text-underline-offset:3px}
.bc-consent div{display:flex;gap:8px;margin-top:12px}
.bc-consent button{border:0;border-radius:999px;padding:7px 16px;font-size:13px;background:var(--paper-2)}
.bc-consent button[data-choice=yes]{background:var(--ink);color:#fff}

@media (max-width:900px){
  .header nav{gap:26px}
  footer{grid-template-columns:1fr;text-align:left}
  footer nav{flex-wrap:wrap}
}
@media (max-width:720px){
  body{font-size:14.5px}
  .header{height:auto;min-height:64px;padding:12px 18px;flex-wrap:wrap;gap:12px}
  .header.is-scrolled{padding:12px 24px}
  .header::before{inset:6px auto 6px 50%}
  .brand span{font-size:26px}.brand img{width:28px;height:28px}
  .header nav{order:3;width:100%;justify-content:space-between;gap:10px;font-size:13.5px;padding:2px 4px 4px}
  .nav-cta{min-height:36px;padding:0 14px;font-size:12.5px}
  .maker{flex-direction:column;align-items:flex-start}
}
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}
  .motion .reveal{opacity:1;transform:none}
}