body{font-family:system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial;padding:20px}#app{max-width:800px;margin:0 auto}textarea{width:100%;font-size:1rem}button{margin-top:8px;padding:8px 12px}pre{background:#f6f8fa;padding:12px;border-radius:6px}