Answers for "how do css keyframes work"

css key frame

div {
  width: 100px;
  height: 100px;
  background: red;
  position: relative;
  animation: mymove 5s infinite;
}

@keyframes mymove {
  0% {top: 0px;}
  50% {top: 50px;}
  75% {top: 40px;}
  100%{top: 0px;}
}

keyframe in css

@keyframes mymove {
  0% {top: 0px;}
  50% {top: 50px;}
  75% {top: 40px;}
  100%{top: 0px;}
}