body {
  font-family: Arial, sans-serif;
  background-color: #1e1e2f;
  color: white;
  text-align: center;
  padding: 20px;
}

h1 {
  margin-bottom: 20px;
}

.game-board {
  display: grid;
  grid-template-columns: repeat(4, 100px);
  gap: 15px;
  justify-content: center;
  margin-top: 20px;
}

.card {
  width: 100px;
  height: 100px;
  background-color: #444;
  font-size: 2rem;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border-radius: 10px;
  transition: background 0.3s;
}

.card.flipped {
  background-color: #00bcd4;
  color: black;
}