.cards {
  display: flex;
  gap: 10px;
  margin: 10px 0;
  min-height: 100px;
}

.card {
  width: 60px;
  height: 90px;
  background: white;
  border-radius: 5px;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 24px;
  color: black;
  font-weight: bold;
}

.card.red {
  color: red;
}

.card.back {
  background: #4a6fa5;
  color: white;
  position: relative;
}

.card.back::before {
  content: "?";
  position: absolute;
}