body {
  font-family: Arial, sans-serif;
  text-align: center;
  background-color: #f0f0f0;
}
h1 {
  color: #333;
}
.game-board {
  display: grid;
  grid-template-columns: repeat(4, 80px);
  gap: 10px;
  justify-content: center;
  margin: 20px auto;
}
.card {
  width: 80px;
  height: 80px;
  background-color: #4caf50;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 30px;
  color: white;
  cursor: pointer;
  border-radius: 10px;
}
.card.flipped {
  background-color: #fff;
  color: #333;
  cursor: default;
}