I just found this project in the FCC github repo,
Basically, you can click in the README link and check out the live version, or running it locally (steps in README), and you get a fantastic experience learning LaTeX and math.
PD after passing the Intro, I realized this is a skeleton, and most of it is empty, but the functionality is perfect.
If you know some latex, some math, some code, it may be worth taking a look.