Change form field font size to all the same

I managed to change font sizes on all form fields EXCEPT the one under 'bericht' as you can see in attached image. Can someone tell me how to change the font size on that last box as well?

Thank you very much in advance!

Can you share link to page where you use form?

https://turtle-rust-s7fb.squarespace.com/contact 

will this work?

13 hours ago, CharlotteD88 said:

https://turtle-rust-s7fb.squarespace.com/contact 

will this work?

 

The site is private. Can you setup an access password? We can check easier

Whoops, offcourse 🙈 https://turtle-rust-s7fb.squarespace.com/contact password 'helpcss'

This is great, thank you very much!