body{font-family:Arial,sans-serif;display:flex;justify-content:center;align-items:center;height:100vh;margin:0;background-color:#f4f4f9}.app{text-align:center;background:#fff;padding:2rem;border-radius:8px;box-shadow:0 4px 6px #0000001a}h1{margin-bottom:1rem;color:#333}.timer{font-size:3rem;margin:1rem 0;color:#333}.controls{display:flex;gap:1rem;margin-bottom:1rem;justify-content:center}.input-group{display:flex;flex-direction:column;align-items:center}label{margin-bottom:.5rem;color:#555}input{padding:.5rem;font-size:1rem;border:1px solid #ccc;border-radius:4px;width:60px;text-align:center}.buttons{display:flex;gap:1rem;justify-content:center}button{padding:.5rem 1rem;font-size:1rem;background-color:#007bff;color:#fff;border:none;border-radius:4px;cursor:pointer}button:disabled{background-color:#ccc;cursor:not-allowed}button:hover:not(:disabled){background-color:#0056b3}