body {
  font-family: Arial, sans-serif;
  text-align: center;
  padding: 20px;
}

.game {
  border: 1px solid #ccc;
  padding: 15px;
  margin: 15px;
}

.locked {
  opacity: 0.5;
}

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