At the moment, only partial changes to the client's styles are possible, and the tool needs to be improved.In your teaspeak client, go to "tools" -» "Modify CSS variables"
You can try my themeYep, saw that, meaning everyone has to work it on his own and it takes time with so many items there. It would be cool and made more sense if one could export the custom css settings to let others use them.
I asked as I was hoping that there were some ready made css sets available.