Gradient overlay CSS w/ using pseudo element.
div:before {
content: "";
position: absolute;
background: -webkit-linear-gradient(350deg, rgba(49, 27, 146, .8) 35%, rgba(125, 38, 205, .75));
background: linear-gradient(350deg, rgba(49, 27, 146, .8) 35%, rgba(125, 38, 205, .75));
width: 100%;
height: 100%;
top: 0;
left: 0;
right: 0;
bottom: 0;
}