body {
  font-family: sans-serif;
  margin: 2rem;
  background-color: #f9f9f9;
  color: #333;
}

header {
  text-align: center;
  margin-bottom: 2rem;
}

button {
  padding: 0.5rem 1rem;
  font-size: 1rem;
  cursor: pointer;
}