Radial gradient mixin
@mixin radial-gradient($from, $to) {
background: -moz-radial-gradient(center, circle cover, $from 0%, $to 100%);
background: -webkit-gradient(radial, center center, 0px, center center, 100%, color-stop(0%, $from), color-stop(100%, $to));
background: -webkit-radial-gradient(center, circle cover, $from 0%, $to 100%);
background: -o-radial-gradient(center, circle cover, $from 0%, $to 100%);
background: -ms-radial-gradient(center, circle cover, $from 0%, $to 100%);
background: radial-gradient(center, circle cover, $from 0%, $to 100%);
background-color: $from;
}