How Can I Change The Post Width

Hi, I’m using lots of tables in my posts.

And, the overall width of the content is rather narrow when I have the sidebar on, which makes the table not look good.

(I have to disable the sidebar in order to get full post width, which is too wide in my opinion, but that’s for a different thread.)

The “problem” is that I want a decent content width while keeping my sidebar on. I really don’t want to disable it.

So I really like this layout: https://demo.tagdiv.com/newspaper_fast/2018/08/16/td-post-social-media-marketing-for-franchises-is-meant-for-women/

I think its width is perfect for my needs.

The question is: Can I increase the content width of the posts on my site to look like the one above, WITHOUT using cloud templates?

I’m using Thrive Architect as my “post builder”, so I can’t use cloud templates.

I would really appreciate any help.

Thanks.

Anyone?
Would really want to solve this one.
Correct display of tables is quite important for me, and I guess for others as well.

Thanks.