:root {
  --bg: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --accent: #0a84ff;
  --card-bg: #f5f5f7;
  --border: #d2d2d7;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --text: #f5f5f7;
    --muted: #98989d;
    --accent: #0a84ff;
    --card-bg: #1c1c1e;
    --border: #2c2c2e;
  }
}

* { box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "SF Pro Display", "Helvetica Neue", Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 32px 24px 64px;
}

header.hero {
  text-align: center;
  padding: 48px 0 32px;
}

header.hero img.icon {
  width: 128px;
  height: 128px;
  border-radius: 28px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.18);
  margin-bottom: 24px;
}

h1 {
  font-size: 42px;
  font-weight: 700;
  margin: 0 0 8px;
  letter-spacing: -0.02em;
}

.subtitle {
  font-size: 20px;
  color: var(--muted);
  margin: 0;
}

h2 {
  font-size: 28px;
  font-weight: 600;
  margin: 48px 0 16px;
  letter-spacing: -0.01em;
}

p { margin: 0 0 16px; }

ul.features {
  list-style: none;
  padding: 0;
  display: grid;
  gap: 12px;
  margin: 24px 0;
}

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

ul.features li strong {
  display: block;
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 4px;
}

ul.features li span {
  color: var(--muted);
  font-size: 15px;
}

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

a:hover { text-decoration: underline; }

dl { margin: 16px 0 0; }
dt { font-weight: 600; margin-top: 20px; }
dd { margin: 6px 0 0; color: var(--muted); }

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

footer a { margin: 0 12px; }
footer p { margin-top: 16px; }