coldfusion.window.create background-color

How do I over-ride the gray screen color in a cfwindow that is created by coldfusion.window.create?

The following JS does not work for IE11 on Windows 8.1:

var

wConfig =new Object(); 

wConfig.bodystyle ="background-color: blue"; //changed it to 'blue'

wConfig.center =true; //center the window on page

ColdFusion.Window.create('mywin', 'test window', 'theUrl.com', wConfig);

The above launches the window fine, but keep the same gray color. The wConfig.center=true works, but not the bodystyle. I have also tried 'bodyStyle' as I hear CF10 is case-senstive(?) for URLs, given this is AJAX.