https://quickref.me/css3.html
https://adam-marsden.co.uk/css-cheat-sheet
https://devhints.io/css

selectors
https://frontend30.com/css-selectors-cheatsheet/

2018
http://css-live.ru/css/pravilnaya-shpargalka-po-css-kaskadu.html
https://medium.com/level-up-web/the-ultimate-guide-to-css-103b0f883de3
    list