There are a couple of things here. First off, I'm not absolutely sure your reference to Stage will work. I would probably just use sym.getStage().getSymbolElement() or something similar to get the jQuery handle. Secondly, you need to make one .css() call per CSS value, as per the jQuery spec: http://api.jquery.com/css/
Hope that helps!
i was trying a different route with:
var vid = sym.$("bkgVIDEO");
vid.html('<video src="_videos/splash_test.mp4" autoplay="yes" loop="yes" width="100%" overflow="hidden" type="video/mp4"></video>');
this brings me very close to the promised land
the only glitch is that the video occupy the entire width (YES!) but only about 60% of the height (NO!)
i tried also including height="100%" but what happen was that the video were lowered a bit
feels so close ...
can you help me get the video 100% both height and width?