Sidebar wonky on reading and tags page

[carisma_sensei]

Hi! I'm having a bit of a problem here. I wanted to edit a layout I made for a friend to use on her community. It has a fixed navigation at the bottom of the page which I don't know if could be causing this problem, but the sidebar looks right on recent entries page but it looks wonky everywhere else.

I have it testing here so you can look through the css. If you could help me out a bit D: I would be very grateful.