also I found some problems in the naming color: RGBa (there is uses RGBA and HSLa (there is used B in stead of L HSBA !!
in the W3schools: information: https://www.w3schools.com/cssref/func_hsla.asp
Also make the border settings more visible place, look to my suggestions.
Also a Photoshop way of working is by mouse making text bigger/smaller. look to this video: https://www.youtube.com/watch?v=Hz2KkgwVnrc
I like more the icons because text in Englisch for people all over the world should be better understanding by icons I think. But still add the possibility to get a video about the element you don’t know anymore how to work with.
Add the office Word icons please (not only by arrow up and down)
Add the possibility to scroll down in the names of fonts, not only a popup!
Add the question mark just the way elements works… so students will better know how to work with the items.
Thanks Karel (teacher webdesign Brussels Belgium)