After doing some troubleshooting, it looks like something is basically up with how bootstrap is handling the toggling. I'm still trying to resolve this issue, but I'm sure this is the right path for me to fix the problem.
Hi! Yes, Toyhouse is using a custom version of Bootstrap 4.??, it's a little hard to pin down the exact version it's using but you should hopefully be able to set the code up using the last version of bootstrap 4—it's not compatible with bootstrap 5, however, as the syntax was changed in a few places and I can't guarantee the layer toggling will behave the same way!