I’m working on the exact same problem right now and was coming here to ask a few questions. I’ve had success changing the font size and attributes by injecting code. It’ll override (but not overwrite) your theme, in a good way if you do it right. Try;
… it changes h1 attributes site-wide. I’ve tried multiple themes with this snippet in place and nothing breaks. Way more efficient than editing a theme, if you want to switch themes later.
You can also add;
… For different attributes. Taking it further, you can change fonts completely by injecting new ones, even web fonts.
Obviously I’m not cranking up to 42px, and there are other modifiers you can use to determine font size, this is just an example. And I’m literally 24 hours into learning CSS so my way is probably very clunky. I’m sure there’s a more elegant path.
If anyone’s reading this, what I’m trying to do is change the font-family and sizes of ‘blog-title’ and ‘blog-description’ only in my site header… I haven’t found a clean way to do that yet. If anyone can point me in the right direction I’d be very appreciative.