[Feedback]My first dark mode WordPress theme

Hello,

I am developing my first dark mode WordPress theme (a custom theme for my new WordPress site, probably not something I'll be distributing).

I was hoping to get some feedback. After staring at the same code/UI/UX for a while I'm sure there are things I've totally overlooked.

It's designed for performance and readability -- maybe not so much flashy appeal. :)

https://wpguineapig.com/

Thank you in advance.