body {
  font-family: 'Arial', sans-serif;
  text-align: center;
  background-color: #f4f4f4;
}

h1 {
  color: #333;
}

.game-board {
  display: grid;
  grid-template-columns: repeat(4, 80px);
  gap: 10px;
  justify-content: center;
  margin-top: 20px;
}

.card {
  width: 80px;
  height: 80px;
  background-color: #3498db;
  color: white;
  font-size: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border-radius: 8px;
}

.card.flipped {
  background-color: #2ecc71;
}