@Mtt I removed the CSS and the theme does indeed look significantly better. And it already looked good before. I saw an update available on the plugins page and so I hit that. Not seeing any further change but I'll give it time; sometimes it takes a while.
@canion mentioned a comparison with Marfa, and the similar Alpine, which I used until very recently. Those are great themes but they seem formal for the kind of casual blogging I do. Your theme seems better suited to a mix of casual and more formal posts, and it does a good job on photos to.
So thank you yet again. And I think I may have seen a donation box on the theme page; I'm going to go look for that right now.