You forget to attach your cart. Ah, fixed now!

uhh it's here now but it was not there before

cool concept. wouldn't mark my level 3 as complete after I finished it. Would be nice if the permanent squares were more distinct than the ones you can toggle white/black. I hope you finish this and make a completed level animation and 'go to next level' button and win screen

Would be nice if you saved the list of completed levels with carddata()/dset()
In “grille 7” I couldn’t figure out what the “groupe blanc 4” was. Maybe display 4/4 in green and say 7/4 in red so we get a chance to understand the rule and monitor the progress.
It’s also not evident that all squares have to be filled. Another text for that would be nice : I’ve quit levels where all black connected and all white connected were ticked and didn’t understand at first why I didn’t get the level completed tick on the level select screen.
Agree with previous commenters that squares and circles could be more distinctive.

EDIT : figured out that groupe blanc 4 means that each orthogonaly connected group of whites has to be of size exactly 4. After that, every level felt easy, except L13 that I don't know how to logically tackle.
Nice puzzle concept. How about a "beige/green/red" highlight for "group too small/right size/too big" ?

@Benoit-belasco
Retried L13, and it's simply impossible as the number of squares to fill is not a multiple of 4.