Reduce width of main content container

Hi there,

I’m currently using generatepress with single posts that have a right-sidebar. My issue is that the content container can become very big when working on bigger screens.

Due to that, the right-sidebar is pushed far to the right of the screen. Since the sidebar contains a table of contents, I want the TOC to be relatively close to the main content.

I’ve tried a great range of things to reduce the width of my content container, but nothing worked. I recorded a video with the issue and what settings I tried:

https://app.screencast.com/Sm1gFMZZ8OfQk

I tried the customizer -> Layout options -> container
Customizer – menu – sidebars
And the single post element

So far no luck. Can you point me in the right direction?

Regards,
Rick