tl;dr - I built a random canva template each day for 7 days to ween myself off Bootstrap.
As a full stack dev, it's easy to spend a lot of time not thinking about the intricate details of HTML and CSS. So to keep my skills & knowledge up-to-date I'm doing a week of quick and dirty design focused builds. Each day I'll be picking a random website template from Canva.com, and building it out in HTML and CSS. The goal is to boost my fundamental skills and get a solid grasp on tools like css-grid and flexbox. Also, it's fun, this kind of web design work is how I first got started as a developer :)
Starting with plain old HTML & CSS. Might go on to do the same thing with JS frameworks (Solid, Svelte, etc) or design systems (Tailwind, Ant, etc).