:root {
  /* Light theme — aligned with STYLE_GUIDE.md. */
  --bg: #ffffff;
  --surface: #ffffff;
  --text: #111827;
  --muted: #6a7280;
  --accent: #1D4ED8;
  --border: #E5E7EB;
  --max-width: 720px;

  color-scheme: light dark;
}

/* Dark theme — auto-applied when the OS / browser prefers dark.
   Same brand accent; dark surface + light text per STYLE_GUIDE.md.
   Wordmark swap is handled by <picture> in the HTML, not CSS. */
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0B1020;
    --surface: #141a2e;
    --text: #F3F4F6;
    --muted: #9aa0b0;
    --accent: #3b82f6;
    --border: #1F2937;
  }
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  font-size: 17px;
}

header, main, footer {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 32px 24px;
}

header {
  padding-bottom: 0;
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

header h1 {
  margin: 0;
  font-size: 28px;
  letter-spacing: -0.02em;
}

header h1 a { color: var(--text); text-decoration: none; }

/* Wordmark — sized via height so the aspect ratio carries the width.
   Header is top-aligned (flex-start) so the nav sits at the top edge
   rather than dropping to the tall wordmark's baseline. */
.wordmark {
  display: block;
  height: 72px;
  width: auto;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  margin-left: 18px;
  font-size: 15px;
}

nav a:hover, nav a.active { color: var(--accent); }

h2 {
  margin-top: 40px;
  font-size: 22px;
  letter-spacing: -0.01em;
}

h3 {
  margin-top: 28px;
  font-size: 17px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

p { margin: 14px 0; }

a { color: var(--accent); }

ul { padding-left: 24px; }
li { margin: 6px 0; }

.hero {
  padding: 48px 0 32px;
}

.hero p.lead {
  font-size: 19px;
  color: var(--muted);
  max-width: 560px;
}

.features {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin: 24px 0 8px;
}

.feature {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 18px 20px;
}

.feature h4 {
  margin: 0 0 6px;
  font-size: 16px;
}

.feature p {
  margin: 0;
  font-size: 15px;
  color: var(--muted);
}

footer {
  border-top: 1px solid var(--border);
  margin-top: 64px;
  padding-top: 24px;
  font-size: 14px;
  color: var(--muted);
}

footer a { color: var(--muted); margin-right: 16px; }

.meta {
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 24px;
}

.legal h2, .legal h3 { margin-top: 32px; }
.legal p { font-size: 16px; }

@media (max-width: 540px) {
  .features { grid-template-columns: 1fr; }
  header { padding: 24px 20px 0; }
  main, footer { padding: 24px 20px; }
}