I have the following style applied to my div element:
div
background-image: -moz-radial-gradient(50% -10%, ellipse closest-corner, rgba(5, 5, 5, 0.7
You just list them one after the other - like this:
background: radial-gradient(top left, rgb(205, 230, 235) 34%, transparent 34%), radial-gradient(center, rgb(205, 230, 235) 34%, transparent 34%);
You can see it working at http://dabblet.com/gist/2759668