:root{color-scheme:light dark}body{font-family:system-ui,-apple-system,sans-serif;max-width:640px;margin:3rem auto;padding:0 1rem}.banner{display:inline-block;padding:.25rem .75rem;border-radius:6px;font-weight:700;font-size:.85rem;letter-spacing:.05em;margin-bottom:1.5rem}.banner.prod{background:#dc2626;color:#fff}.banner.dev{background:#16a34a;color:#fff}form{display:flex;gap:.5rem;margin-bottom:1.5rem}input{flex:1 1;padding:.5rem}button{padding:.5rem 1rem}ul{padding-left:1.25rem}