:root {
  --bg: #f5f5f7;
  --fg: #1d1d1f;
  --muted: #6e6e73;
  --card: #ffffff;
  --border: #d2d2d7;
  --accent: #0071e3;
  --accent-fg: #ffffff;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --fg: #f5f5f7;
    --muted: #a1a1a6;
    --card: #1c1c1e;
    --border: #38383a;
    --accent: #2997ff;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", system-ui, sans-serif;
  line-height: 1.5;
}

main {
  max-width: 960px;
  margin: 0 auto;
  padding: 72px 16px 48px;
}

.hero {
  text-align: center;
}

.hero h1 {
  font-size: clamp(2.5rem, 7vw, 4rem);
  letter-spacing: -0.02em;
  margin: 16px 0 8px;
}

.tagline {
  font-size: 1.25rem;
  color: var(--muted);
  max-width: 36ch;
  margin: 0 auto;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-top: 32px;
}

.button {
  padding: 10px 22px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--fg);
  text-decoration: none;
  font-weight: 500;
}

.button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--accent-fg);
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 16px;
  margin-top: 80px;
}

.features article {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px;
}

.features h2 {
  font-size: 1.05rem;
  margin: 0 0 6px;
}

.features p {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

footer {
  margin-top: 64px;
  text-align: center;
  color: var(--muted);
  font-size: 0.85rem;
}