itch.io

And of course, let me know when you do it!

Sorry for being late in this answer. Life got crazy. 

So... This game is CC-BY. You can use however you want, just need to give the credit by saying where you found the system, who wrote it, something like that.

I really loved!

This is one of the best thing I ever saw. Did you write this in LaTeX?

You're right!

All of those links are going to https://lucasrolim.itch.io/

https://rodrigo-o.itch.io/ → This is my page

Thank you so much! 🥰

There was an error in the first book, 6+ should be 7+!