body { font: 16px/1.5 system-ui, sans-serif; margin: 0; background: #fafafa; color: #222; }
main { max-width: 40rem; margin: 2rem auto; padding: 0 1rem; }
nav a { margin-right: 1rem; }
pre { background: #fff; border: 1px solid #ddd; padding: 1rem; overflow-x: auto; }
input { font: inherit; padding: .25rem .5rem; }