:root { color-scheme: light dark; }
body {
  margin: 0;
  font: 18px/1.5 system-ui, sans-serif;
  background: Canvas;
  color: CanvasText;
}
main { max-width: 32rem; margin: 0 auto; padding: 1.5rem 1rem; }
h1 { margin: 0 0 1rem; font-size: 2rem; }