body {

     background: linear-gradient(-45deg, #ee7752, #e73c7e, #23a6d5, #23d5ab);

     background-size: 400% 400%;

     animation: gradient 45s ease infinite;

     height: 100vh;

 }

 

 body {

     display: block;

     margin: 8px;

 }

 0% {

     background-position: 0% 50%;

 }

 50% {

     background-position: 100% 50%;

 }

 

 100% {

     background-position: 0% 50%;

 }