:root {
  --bg: #f4f8fc;
  --surface: #ffffff;
  --text: #0f1b2d;
  --muted: #5b6b80;
  --accent: #1a8cff;
  --accent-ink: #ffffff;
  --border: rgba(15, 27, 45, 0.10);
  --shadow: 0 10px 30px rgba(15, 27, 45, 0.08);
  --radius: 20px;
  --max: 1040px;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --surface: #131c2e;
    --text: #eef3fa;
    --muted: #9aa9bd;
    --accent: #4aa8ff;
    --border: rgba(255, 255, 255, 0.10);
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
  }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
img { max-width: 100%; display: block; }

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 20px; }

/* Header */
.site-header { position: sticky; top: 0; z-index: 10; background: color-mix(in srgb, var(--bg) 85%, transparent); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); }
.site-header .wrap { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 4px 18px; min-height: 64px; padding-top: 10px; padding-bottom: 10px; }
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 19px; color: var(--text); white-space: nowrap; }
.brand img { width: 34px; height: 34px; border-radius: 9px; }
.brand:hover { text-decoration: none; }
nav { white-space: nowrap; margin-left: -12px; }
nav a { display: inline-block; padding: 4px 0; }
nav a { color: var(--muted); margin-left: 22px; font-size: 15px; }
nav a:hover, nav a[aria-current="page"] { color: var(--text); text-decoration: none; }

/* Hero */
.hero { padding-top: 72px; padding-bottom: 40px; text-align: center; }
.hero img.icon { width: 112px; height: 112px; border-radius: 26px; margin: 0 auto 22px; box-shadow: var(--shadow); }
.hero h1 { font-size: clamp(34px, 6vw, 56px); line-height: 1.1; margin: 0 0 14px; letter-spacing: -0.02em; }
.hero p.lead { font-size: clamp(18px, 2.4vw, 21px); color: var(--muted); max-width: 640px; margin: 0 auto 28px; }
.cta { display: inline-flex; align-items: center; gap: 10px; background: var(--text); color: var(--bg); padding: 14px 24px; border-radius: 14px; font-weight: 600; }
.cta:hover { text-decoration: none; opacity: 0.9; }
.cta-note { display: block; margin-top: 12px; font-size: 14px; color: var(--muted); }

/* Feature grid */
section { padding: 40px 0; }
section h2 { font-size: clamp(26px, 4vw, 34px); text-align: center; margin: 0 0 8px; letter-spacing: -0.01em; }
section p.sub { text-align: center; color: var(--muted); margin: 0 auto 32px; max-width: 620px; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(280px, 100%), 1fr)); gap: 18px; }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; box-shadow: var(--shadow); }
.card .emoji { font-size: 28px; line-height: 1; }
.card h3 { margin: 12px 0 6px; font-size: 19px; }
.card p { margin: 0; color: var(--muted); font-size: 16px; }
.tag { display: inline-block; font-size: 11px; font-weight: 700; letter-spacing: 0.04em; padding: 2px 8px; border-radius: 999px; background: color-mix(in srgb, var(--accent) 15%, transparent); color: var(--accent); vertical-align: middle; margin-left: 6px; }
.tag.preview { background: rgba(255, 149, 0, 0.16); color: #e08600; }

/* Privacy band */
.band { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 36px 28px; text-align: center; box-shadow: var(--shadow); }
.band h2 { margin-bottom: 10px; }
.band p { color: var(--muted); max-width: 700px; margin: 0 auto; }

/* Long-form pages */
.page { padding: 56px 0 24px; }
.page .wrap { max-width: 760px; }
.page h1 { font-size: clamp(32px, 5vw, 44px); margin: 0 0 6px; letter-spacing: -0.02em; }
.page .updated { color: var(--muted); margin: 0 0 28px; }
.page h2 { font-size: 23px; margin: 36px 0 8px; }
.page h3 { font-size: 18px; margin: 22px 0 4px; }
.page p, .page li { color: var(--text); }
.page ul { padding-left: 22px; }
.page li { margin: 6px 0; }
.callout { background: var(--surface); border: 1px solid var(--border); border-radius: 16px; padding: 18px 20px; margin: 18px 0; }
details { background: var(--surface); border: 1px solid var(--border); border-radius: 14px; padding: 14px 18px; margin: 10px 0; }
details summary { cursor: pointer; font-weight: 600; }
details p { margin: 10px 0 2px; color: var(--muted); }

/* Footer */
footer { border-top: 1px solid var(--border); margin-top: 48px; padding: 28px 0 40px; color: var(--muted); font-size: 14px; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 14px 24px; justify-content: space-between; }
footer a { color: var(--muted); }

body { overflow-x: hidden; }
@media (max-width: 560px) {
  nav a { margin-left: 12px; font-size: 14px; }
  .brand { font-size: 17px; }
  .brand img { width: 30px; height: 30px; }
  .hero { padding-top: 48px; }
}