body {
  animation-name: bgColorChange;
  animation-duration: 10s;
/*   animation-fill-mode: forwards; */
/*   animation-iteration-count: infinite; */
/*   animation-delay: 2s; */
}
@keyframes bgColorChange {
    0% { background-color: red; }
   25% { background-color: orange; }
   50% { background-color: yellow; }
   75% { background-color: green; }
  100% { background-color: blue; }
}