Così?
background-image: -ms-radial-gradient(center, circle farthest-corner, #FFFFFF 0%, #00A3EF 100%);
background-image: -moz-radial-gradient(center, circle farthest-corner, #FFFFFF 0%, #00A3EF 100%);
background-image: -o-radial-gradient(center, circle farthest-corner, #FFFFFF 0%, #00A3EF 100%);
background-image: -webkit-gradient(radial, center center, 0, center center, 487, color-stop(0, #FFFFFF), color-stop(1, #00A3EF));
background-image: -webkit-radial-gradient(center, circle farthest-corner, #FFFFFF 0%, #00A3EF 100%);
background-image: radial-gradient(circle farthest-corner at center, #FFFFFF 0%, #00A3EF 100%);
P.S. Non ho potuto usare il tag code perchè mi da errrore