/* Fewer site — the app's own darkroom palette (DesignSystem/Theme.swift), so the page
   and the screenshots on it are the same colours. Neutral ground, saturation spent on
   one amber number and one blue action. */
:root {
  --surface: #FAFAF8;
  --raised: #FFFFFF;
  --ink: #111113;
  --muted: #6B6B70;
  --faint: #A8A8AE;
  --hair: #E2E2DE;
  --keep: #0A84FF;
  --accent: #C98A25;       /* amber, darkened for AA on the light ground */
  --accent-soft: rgba(232, 163, 61, 0.14);
}
@media (prefers-color-scheme: dark) {
  :root {
    --surface: #0E0E10;
    --raised: #1A1A1D;
    --ink: #F5F5F7;
    --muted: #8A8A90;
    --faint: #5C5C63;
    --hair: #2A2A2E;
    --keep: #3A9BFF;
    --accent: #F0B054;
    --accent-soft: rgba(240, 176, 84, 0.16);
  }
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--surface);
  color: var(--ink);
  font: 16px/1.7 -apple-system, "PingFang SC", "Hiragino Sans GB", "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
}
.wrap { max-width: 1020px; margin: 0 auto; padding: 0 24px; }
a { color: var(--keep); text-decoration: none; }
a:hover { text-decoration: underline; }
a:focus-visible, button:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--keep); outline-offset: 3px; border-radius: 4px;
}
/* Both languages are in the DOM; html[data-lang] decides which shows. */
html[data-lang="zh"] .en { display: none; }
html[data-lang="en"] .zh { display: none; }

/* nav */
.nav { display: flex; align-items: center; gap: 22px; padding: 18px 0; border-bottom: 1px solid var(--hair); }
.brand { font-size: 22px; font-weight: 700; color: var(--ink); margin-right: auto; letter-spacing: -0.01em; }
.brand:hover { text-decoration: none; }
.nav a.navlink { color: var(--muted); font-size: 15px; }
.nav a.navlink:hover { color: var(--ink); text-decoration: none; }
.langbtn {
  border: 1px solid var(--hair); background: transparent; color: var(--muted);
  border-radius: 999px; padding: 5px 14px; font-size: 13px; cursor: pointer; font-family: inherit;
}
.langbtn:hover { border-color: var(--ink); color: var(--ink); }

/* numerals: rounded like the app's hero figure */
.num { font-family: "SF Pro Rounded", -apple-system, system-ui, sans-serif; font-variant-numeric: tabular-nums; font-weight: 600; }

/* cards */
.card { background: var(--raised); border: 1px solid var(--hair); border-radius: 20px; padding: 22px 24px; }

/* buttons */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 13px 22px; border-radius: 14px; font-weight: 600; font-size: 15px; }
.btn-primary { background: var(--keep); color: #fff; }
.btn-primary:hover { text-decoration: none; filter: brightness(1.05); }
.btn-ghost { border: 1px solid var(--hair); color: var(--ink); background: var(--raised); }
.btn-ghost:hover { text-decoration: none; border-color: var(--ink); }

/* footer */
.footer { display: flex; flex-wrap: wrap; gap: 8px 22px; align-items: center;
  padding: 28px 0 44px; margin-top: 64px; border-top: 1px solid var(--hair);
  color: var(--muted); font-size: 14px; }
.footer a { color: var(--muted); }
.footer a:hover { color: var(--ink); }