body {
  background: linear-gradient(334deg, #00a7ff, #9400ff, #0042ff);
  background-size: 600% 600%;
  -webkit-animation: bgGradient 9s ease infinite;
  -moz-animation: bgGradient 9s ease infinite;
  -o-animation: bgGradient 9s ease infinite;
  animation: bgGradient 9s ease infinite;
}

@keyframes bgGradient {
  0% {
    background-position: 13% 0%;
  }
  50% {
    background-position: 88% 100%;
  }
  100% {
    background-position: 13% 0%;
  }
}