#star {
  background-color: navy;
  position: relative;
  animation-name: movement;
  animation-duration: 15s;
  animation-iteration-count: infinite;
  
}

@keyframes movement {
  0% {
    left: 0;
    top: 0;
    background-color: navy;
    transform: scale(1);
  }
  25% {
    left: 250px;
    top: 0;
    background-color: purple;
    transform: scale(1);
  }
  50% {
    left: 300px;
    top: 300px;
    background-color: green;
    transform: scale(1);
  }
  75% {
    left: 0;
    top: 400px;
    background-color: red;
    transform: scale(1);
  }
  100% {
    left: 0;
    top: 0;
    background-color: navy;
    transform: scale(1);
  }
}