Set browser (not stage) background to gradient

HI...

Very noob to css and all....

I am trying to set my browseer background to a radial gradient...but I dont know the proper syntax.

I am trying to reconcile this pages code

http://www.w3schools.com/css/css3_gradients.asp....

#grad

{

/* Safari 5.1 to 6.0 */

background: -webkit-repeating-linear-gradient(red, yellow 10%, green 20%);

/* Opera 11.1 to 12.0 */

background: -o-repeating-linear-gradient(red, yellow 10%, green 20%);

/* Firefox 3.6 to 15 */

background: -moz-repeating-linear-gradient(red, yellow 10%, green 20%);

/* Standard syntax */

background: repeating-linear-gradient(red, yellow 10%, green 20%);

}

and somehow inject it into a composition ready statement like this

$("body").css("background-color","#000");

Ideally i would like a gradient to border the edges of the stage, just in the browser background instead of a solid color

Thanks