Rrandom color changing background color webkit chrome

<style>
    body {background-color: yellow;} 
</style>-

---------------------

$(function() {
    if ($.browser.webkit) {
        $("body").css("background", "#4d4d4d");
    }
});

----------------------

<style type="text/css">
    body {
    -webkit-animation: colorchange 60s infinite; 
    animation: colorchange 20s infinite;
}
@-webkit-keyframes colorchange {
     0%  {background: #33FFF3;}
    25%  {background: #78281F;}
    50%  {background: #117A65;}
    75%  {background: #DC7633;}
    100% {background: #9B59B6;}
}
@keyframes colorchange {
     0%  {background: #33FFF3;}
    25%  {background: #78281F;}
    50%  {background: #117A65;}
    75%  {background: #DC7633;}
    100% {background: #9B59B6;}
}   

</style>