I installed a theme here https://forums.delphiforums.com/youngrestless and it is showing as Zeta for some reasosn. I have never done a zeta theme before, and the forum was in classic mode before I installed it. I can't seem to find in controls how to change it to classic...help please!

The forum is showing as Classic, did you find the setting?

It shows as zeta on my laptop. I don't know where the setting is Gunter...can you tell me?

Did you see it as Classic on the laptop before? Delphi's showing you Zeta mobile (I see Zeta on my phone). 

If you go to Controls in that forum you will see (last option) Classic Control Center. That gives you access to the Style Sheet editor and the Colors and Fonts page.

She's not the Host so will not see that option. I think Delphi is seeing her laptop as a smaller screen. 
Does that happen if she's Zoomed the view?  

This has never happened to me Kid. Not at any forum. I don't get it. Will poke around the back end some more.

Are you Zoomed or did you shrink the Window of you browser? Changed your browser? 
Or - updated it? Firefox and I think Chrome moved to version 100 recently I wonder if that had an effect. 

Can you switch to Desktop Site in browser Settings?

I always use chrome as my browser. I pulled up firefox to check it and it still shows as a zeta forum. I changed the browser to 100% and it makes no difference as to the look of the forum. The theme shows as classic in my test forum, so I know everything was fine with it. It was only after I installed it at the main forum when it changed. The previous theme was classic. All my themes are classic. I don't know what to do. :(