.card-flip {
  width: 100%;
  height: 300px;
  margin: auto;
}

.card-flip .front,
.card-flip .back {
  width: 100%;
  height: 100%;
  border: 1px solid #ddd;
  border-radius: 10px;
  background: var(--color-fondo);
  overflow: hidden;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}