What courses can you recommend to systematize knowledge of HTML+CSS?

Question

css

I have quite a lot of knowledge in these areas, but they are all scattered. I would like to somehow systematize, fill in the gaps. What courses or maybe articles/books can you recommend? It is desirable that we are talking about HTML5 and CSS3, although catching up on this, based on knowledge of earlier versions, is generally not difficult.
Thanks in advance

Answer 1

https://www.w3schools.com/
https://htmlacademy.ru/ (intensive webinar)
and read fresh books in English 2017 and 2018+

Answer 2

The best of all will be of course w3schools.com , and also freecodecamp.com is very good