I'm trying to create a div that takes up the entirety of the right side of the sidebar. I'm correctly making the height as long as it needs to be, but the width is only as big as the content that is inside it, even tho I've been setting the width to 100%. Can anyone help me figure this out?

Here is my code:
https://gist.github.com/DylanDevelops/b9f3f5e2f106751f03ecd637e3cfa8e0