animate.color.css

/* Keyfram-licious animation */
@-webkit-keyframes colors {
  0% {background-color: #39f;}
 15% {background-color: #F246C9;}
  30% {background-color: #4453F2;}
  45% {background-color: #44F262;}
  60% {background-color: #F257D4;}
  75% {background-color: #EDF255;}
  90% {background-color: #F20006;}
  100% {background-color: #39f;}
}

.border,.rain{
  -webkit-animation-direction: normal;
  -webkit-animation-duration: 20s;
  -webkit-animation-iteration-count: infinite;
  -webkit-animation-name: colors;
  -webkit-animation-timing-function: ease;
}