Okay, a search turned up a few topics, but nothing that got resolved in a way that was well-explained. :-(
Tweaking Minimalism, I've made a page with a #999 page background and a white post background. The problem, of course, is when there's very little content on the page; instead of a full vertical white area in the middle of a gray page, I get a white rectangle at the top of the page surrounded by gray on three sides.
Note: I'm not using the word "columns" because I don't want to confuse the issue with a discussion of two- or three-column layouts.
It seems like
min-height: 100% (or perhaps simply
height: 100% should solve this, but either it doesn't or I don't know where to put it.
Help! Thanks in advance, all. :-)