It appears that all themes scroll at the page level. I would like a page that has a fixed navigation sidebar and a scrollable main content. I tried "style = overflow : auto" in the div that contains the definition but that does not seem to work.

Essentially, as I add blocks to the new area 'main' I would like that area to scroll and both the navigation sidebar and page length would remain fixed. The objective is to have the left side navigation always present regardless of the number of blocks added to the right side content.

That might be simple php or css but I can't seem to find examples to review. It might also be a question about how areas and blocks work. I thought it best to make it a theme question to begin with. If so, could someone point me in the right direction. Thanks