Cacher is the code snippet organizer for pro developers

https://tinyjpg.com/

http://expressprefixr.herokuapp.com/

http://difff.jp/

http://html-coding.co.jp/cheatsheet/name/id_class.php

https://nj-clucker.com/css-content-property-mojibake/

http://www.simplecss.eu/

https://docs.emmet.io/cheat-sheet/