I don't know if it's called a "stage" or what, but I need to know the size of the work area. To put it another way, what size would a background be to fill the whole work area or stage or screen - whatever you want to call it. Whenever I load a background there is white space. I definitely don't want that in my finished video. So what size would the background have to be to fit 100% both horizontally and vertically? Is this related to the output size when I save or export a project? Thanks.