body {
  font-family: Arial, sans-serif;
  background-color: #f9f9f9;
  color: #111;
  text-align: center;
  padding-top: 80px;
  transition: background-color 0.3s ease;
}

button {
  padding: 10px 20px;
  font-size: 16px;
  cursor: pointer;
}

.dark {
  background-color: #111;
  color: #f9f9f9;
}