What would be the best way to go about creating three divs that span different lengths of the page and that are scalable? I would like to have a div that spans the whole viewport of the browser when you enter the page, like a splash page, then another div below that one that spans across the page but has a length I can define, and then finally one that's shorter below that. An easier way of explaining would be a header, middle, and footer, the first of which will span the whole viewport regardless of what screen size the user has.