.gradient {
    height: 100%;
    width: 100%;
    left:0;
    right: 0;
    top: 0;
    bottom: 0;
    position: absolute;
    background: radial-gradient(circle at bottom center, #ff2400 500px, #e81d1d, #e8b71d, #e3e81d, #1de840, #1ddde8, #2b1de8, #dd00f3, #dd00f3);
    background-size: 1800% 1800%;

    -webkit-animation: rainbow 150s ease infinite;
    -z-animation: rainbow 150s ease infinite;
    -o-animation: rainbow 150s ease infinite;
    animation: rainbow 150s ease infinite;}

@-webkit-keyframes rainbow {
    0%{background-position:0% 82%}
    50%{background-position:100% 19%}
    100%{background-position:0% 82%}
}
@-moz-keyframes rainbow {
    0%{background-position:0% 82%}
    50%{background-position:100% 19%}
    100%{background-position:0% 82%}
}
@-o-keyframes rainbow {
    0%{background-position:0% 82%}
    50%{background-position:100% 19%}
    100%{background-position:0% 82%}
}
@keyframes rainbow {
    0%{background-position:0% 82%}
    50%{background-position:100% 19%}
    100%{background-position:0% 82%}
}