body{font-family:system-ui,sans-serif;max-width:720px;margin:40px auto;padding:0 16px;color:#1c1c1c}h1{font-size:22px}button{font:inherit;padding:10px 16px;border-radius:8px;border:1px solid #333;background:#111;color:#fff;cursor:pointer}button.secondary{background:#fff;color:#111}button:disabled{opacity:.5;cursor:default}pre{background:#f4f4f4;padding:12px;border-radius:8px;overflow:auto;font-size:12px}.row{display:flex;gap:8px;flex-wrap:wrap;margin:16px 0}.muted{color:#666;font-size:14px}.err{color:#b00020}