+1 to HillRat's answer (especially hacking around in Codepen). On top of his, I want to plug the Mozilla Web Docs [0]. They're absolutely wonderful to reference

+1 to HillRat's answer (especially hacking around in Codepen). On top of his, I want to plug the Mozilla Web Docs [0]. They're absolutely wonderful to reference for all your CSS needs, especially if you learn well from reading the docs. On top of that, they have excellent tutorials as well. I would consider checking out their one on CSS [1], you might find it easier to get through than an O'Reilly book. A little unrelated but as someone who also loves their C++ and low-level programming I really enjoyed Lin Clark's articles on Firefox's Stylo [2] and WebRender [3], I think they do a great job of intuitively explaining the back-end behind CSS rendering, if that's of any interest to you. [0] https://developer.mozilla.org/en-US/ https://developer.mozilla.org/en-US/ [1] https://developer.mozilla.org/en-US/docs/Learn/CSS https://developer.mozilla.org/en-US/docs/Learn/CSS [2] https://hacks.mozilla.org/2017/08/inside-a-super-fast-css-engine-quantum-css-aka-stylo/ https://hacks.mozilla.org/2017/08/inside-a-super-fast-css-en... [3] https://hacks.mozilla.org/2017/10/the-whole-web-at-maximum-fps-how-webrender-gets-rid-of-jank/ https://hacks.mozilla.org/2017/10/the-whole-web-at-maximum-f...