<div class="ball"></div>
.ball {
  border-radius: 50%;
  width: 200px;
  height: 200px;
  border: 2px solid #000;
  animation-name: grow;
  animation-duration: 2s; 
  animation-timing-function: ease-out; 
  animation-delay: 0;
  animation-direction: alternate;
  animation-iteration-count: infinite;
  animation-fill-mode: none;
  animation-play-state: running;
}

@keyframes grow {
  0% {
    transform: scale(.5);
    background-color: yellow;
    border-radius: 100%;
  }
  50% {
    background-color: purple;
  }
  100% {
    transform: scale(1.5);
    background-color: pink;
  }
}

body,
html {
  height: 100%;
}

body {
  display: flex;
  justify-content: center;
  margin-top: 150px;
  background-color: #D2F8D2; 
}

External CSS

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External JavaScript

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