:root {
  color-scheme: light dark;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
  color: #172033;
  background: #f5f7fb;
}

* { box-sizing: border-box; }

body { margin: 0; }

main {
  width: min(760px, calc(100% - 40px));
  margin: 64px auto;
  padding: 48px;
  background: #fff;
  border: 1px solid #dfe4ee;
  border-radius: 20px;
  box-shadow: 0 16px 48px rgba(28, 39, 64, 0.08);
}

h1, h2 { line-height: 1.25; }
h1 { margin-top: 0; font-size: clamp(2rem, 6vw, 3.25rem); }
h2 { margin-top: 2.2rem; }
p, li { max-width: 68ch; }
a { color: #2457d6; }

.eyebrow {
  margin-bottom: 0.5rem;
  color: #52627a;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.notice {
  margin: 2rem 0;
  padding: 1rem 1.2rem;
  background: #eef3ff;
  border-left: 4px solid #2457d6;
  border-radius: 8px;
}

nav, footer {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

footer {
  margin-top: 3rem;
  padding-top: 1.5rem;
  border-top: 1px solid #dfe4ee;
  color: #52627a;
  font-size: 0.9rem;
}

@media (max-width: 640px) {
  main { margin: 20px auto; padding: 28px 22px; }
}

@media (prefers-color-scheme: dark) {
  :root { color: #e9edf6; background: #111725; }
  main { background: #182033; border-color: #303c55; box-shadow: none; }
  a { color: #9ab5ff; }
  .eyebrow, footer { color: #b6c0d3; }
  .notice { background: #202d4a; border-left-color: #9ab5ff; }
  footer { border-color: #303c55; }
}