:root { color-scheme: light dark; }
body { max-width: 42rem; margin: 0 auto; padding: 1.5rem 1rem 3rem;
       font: 16px/1.6 -apple-system, "Segoe UI", Roboto, sans-serif; }
header h1 { margin-bottom: .25rem; font-size: 1.6rem; }
nav { font-size: .9rem; margin-bottom: 2rem; }
nav a { color: inherit; }
article { margin-bottom: 1.75rem; }
article h2, article h3 { margin-bottom: .35rem; }
footer { margin-top: 3rem; font-size: .85rem; opacity: .65; border-top: 1px solid; padding-top: 1rem; }