How do I put an image to the background instead of just a colour?

I am making a web app and i would like to know, if i can put an image outside of the viewable area?

tiledbackround and place it on the lowest layer in ur game or at the bottom of ur layer. bellow everything else. i dont think u can set a image as BG in the settings directly yet. maybe a feature for the future? Ashley

You can either change the fullscreen mode to fill the entire display and then you can control everything that is drawn (but have to deal with different aspect ratios), or you can use HTML/CSS to customize what appears in the background. The area with the background color is just the HTML document background, and the project appears on a canvas element within that.