Problem with CSS

So I have a theme that I tweaked a little to suit my needs.Everything works very well on my pages but when I go to a category page,my sidebar is not in the right of the page,but beneath all of the posts in that category.When I try to open other pages it works like a charm.

Here is my CSS file:
https://pastie.org/3774331

The webpage that doesn’t look right:
https://entirecraft.com/mc/category/rules/

Example of page that looks right:
https://entirecraft.com/mc/
https://entirecraft.com/mc/general-rules/

Hope you can help me with this problem.I tried tweaking the CSS for 3 hours now with no luck(I learned CSS of off youtube)