pop vs unpop animate class

.anim-fill-both {
  animation-fill-mode: forwards;
}

//animations
@keyframes pop {
  0% {
    transform: scale(0.9) translateZ(0);
  }
  100% {
    transform: scale(1) translateZ(0);
  }
}

.pop {
  animation-name: pop;
  @extend .anim-fill-both;
}

@keyframes unpop {
  0% {
    transform: scale(1) translateZ(0);
  }
  100% {
    transform: scale(0.9) translateZ(0);
  }
}

.unpop {
  animation-name: unpop;
  @extend .anim-fill-both;
}