.style1 > div { animation-name: style1; }
.style2 > div { animation-name: style2; }
.style3 > div { animation-name: style3; }
.style4 > div { animation-name: style4; }

.is-animate > div {
  animation-duration: 1s;
  animation-timing-function: ease-in-out;
  animation-iteration-count: infinite;
}