my.css

background: linear-gradient(180deg, #2489db, #24dbbc, #24db2b, #dbbf24, #db6624, #db2453, #db24a4, #9124db);
background-size: 1600% 1600%;
-webkit-animation: home-button 57s ease infinite;
-moz-animation: home-button 57s ease infinite;
-o-animation: home-button 57s ease infinite;
animation: home-button 57s ease infinite;
@-webkit-keyframes home-button {
    0%{background-position:71% 0%}
    50%{background-position:30% 100%}
    100%{background-position:71% 0%}