How to use variables.scss?

Hey Guys.
I’m trying to set the variable $split-pane-side-max-width to sth lower but i can’t make it work.
I put it in my variables.scss file and tried different ways to write it down.

What is the correct way to define the variable new?

Btw i changed some of These “Colors” and I can use them without a Problem.

Thank you

Ok I made it. I just figured out, that I had to Play around with the “min” value too…