変身の呪い

#box {
  width: 100px;
  height: 100px;
  background: steelblue;
  animation: henshin 0.5s infinite alternate;
}

@keyframes henshin {
  from {
    background: steelblue;
    transform: scale(1);
  }
  to {
    background: tomato;
    transform: scale(1.5);
  }
}

@keyframes henshin {
  from {
    background: steelblue;
    transform: scale(1);
  }
  to {
    background: tomato;
    transform: scale(1.5);
  }
}