body, #logo h1 a, ul#menu li.on {background-color: #39f !important;}
@-webkit-keyframes colours {
	  0% {background-color: #39f;}
	 15% {background-color: #8bc5d1;}
	 30% {background-color: #f8cb4a;}
	 45% {background-color: #95b850;}
	 60% {background-color: #944893;}
	 75% {background-color: #c71f00;}
	 90% {background-color: #bdb280;}
	100% {background-color: #39f;}
}
body, #logo h1 a, ul#menu li.on {
	-webkit-animation-direction: normal;
	-webkit-animation-duration: 60s;
	-webkit-animation-iteration-count: infinite;
	-webkit-animation-name: colours;
	-webkit-animation-timing-function: ease;
}

http://www.massiveblue.com/

Color-transition loop  from the massiveblue homepage

Webkit Color Transition Loop

css, CSS3

CSS