[0-_-0]

I just went down the rabbit hole of Venn diagrams, and emerged with one for 7 sets:

https://i.stack.imgur.com/kImwq.png

[carapace]

That's truly awesome. Cheers!

Check out Lewis Carol's Logic Game:

https://www.cut-the-knot.org/LewisCarroll/tridiagram.shtml