:root { color-scheme: light dark; }
body { margin: 0; font-family: system-ui, sans-serif; line-height: 1.7; background: Canvas; color: CanvasText; }
main { max-width: 42rem; margin: 0 auto; padding: 2rem 1rem; }
h1 { font-size: 1.6rem; }
h2 { font-size: 1.15rem; margin-top: 2rem; }