@keyframes colorChange {
    from {
        background: -webkit-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* Chrome 10+, Saf5.1+ */
        background:    -moz-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* FF3.6+ */
        background:     -ms-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* IE10 */
        background:      -o-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* Opera 11.10+ */
        background:         linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* W3C */
    }
    to {
        background: -webkit-linear-gradient(90deg, #FFC837 10%, #FF8008 90%); /* Chrome 10+, Saf5.1+ */
        background:    -moz-linear-gradient(90deg, #FFC837 10%, #FF8008 90%); /* FF3.6+ */
        background:     -ms-linear-gradient(90deg, #FFC837 10%, #FF8008 90%); /* IE10 */
        background:      -o-linear-gradient(90deg, #FFC837 10%, #FF8008 90%); /* Opera 11.10+ */
        background:         linear-gradient(90deg, #FFC837 10%, #FF8008 90%); /* W3C */
    }
}

body {
    width: 100%;
    height: 100%;
    background: -webkit-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* Chrome 10+, Saf5.1+ */
    background:    -moz-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* FF3.6+ */
    background:     -ms-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* IE10 */
    background:      -o-linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* Opera 11.10+ */
    background:         linear-gradient(90deg, #FF8008 10%, #FFC837 90%); /* W3C */

    animation-duration: 3s;
    animation-name: colorChange;
    animation-iteration-count: infinite;
    animation-direction: alternate;
}