:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #1c1f26;
  --muted: #5b6270;
  --line: #e3e6ec;
  --card: #f5f7fa;
  --accent: #1a8cff;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1118;
    --fg: #e8ebf1;
    --muted: #9aa3b2;
    --line: #232a36;
    --card: #151b25;
    --accent: #3fb3ff;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
}
main { max-width: 760px; margin: 0 auto; padding: 56px 20px 80px; }
a { color: var(--accent); }
header.hero { text-align: center; margin-bottom: 48px; }
header.hero img { width: 128px; height: 128px; }
header.hero h1 { font-size: 40px; margin: 12px 0 4px; letter-spacing: -0.02em; }
header.hero p { color: var(--muted); font-size: 20px; margin: 0; }
.buttons { margin-top: 24px; display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.button {
  display: inline-block; padding: 10px 20px; border-radius: 10px;
  background: var(--accent); color: #fff; text-decoration: none; font-weight: 600;
}
.button.secondary { background: var(--card); color: var(--fg); border: 1px solid var(--line); }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px; }
.card h3 { margin: 0 0 6px; font-size: 17px; }
.card p { margin: 0; color: var(--muted); font-size: 15px; }
h2 { margin-top: 48px; font-size: 24px; }
.prose h1 { font-size: 32px; margin-bottom: 0; }
.prose em:first-of-type { color: var(--muted); }
footer { max-width: 760px; margin: 0 auto; padding: 24px 20px 48px; color: var(--muted); font-size: 14px; border-top: 1px solid var(--line); }
footer a { color: inherit; }