SVT Play Bakgrund CSS3

.bakgroundGradient {
    background: -webkit-linear-gradient(black 31%, white 46%);
    background: -moz-linear-gradient(black 31%, white 46%);
    background: -ms-linear-gradient(black 31%, white 46%);
    background: -o-linear-gradient(black 31%, white 46%);
    background: linear-gradient(black 31%, white 46%);
    width: 100%;
    height: 100%;
    position: fixed;
    top: 0;
    left: 0;
    z-index: -999;
}