Any idea how to collapse

[Robert9]

I have still no idea what i want to do with the cats; but maybe i can collapse them.
I was sure to find an add-on the watch how this could be done, but my search failed.
I can start doing this with own css, but i would prefer the things that are normally user everywhere else. So my question: is there anything useful to know for me?

 

[Bob]

So my question: is there anything useful to know for me?

Before trying to customize anything, I'd suggest reverse engineering it so that you fully understand how it is designed. That is the same advice that I give anyone that wants to customize something.

 

[Robert9]

The solution is much more easy. I show it left under x pixel and right above.
So i have it on top at the mobile and on the right on larger screens.