How to make step fill/cover screen

[McShaman]

I would like to know how to make a step fill the screen no mater what size or aspect ratio the users screen.

I have tried various things with the viewPort property but no matter what settings I put in it will only fit to the width or height of the screen not both. So depending on the users aspect ratio there is white space above and below or left and right.

How can I get the step to fill/cover the screen? I don't mind if it will be cutting off some information.