Need CSS proofreading!

It's my first CSS attempt. I based off myself from a template and I need some of you to check if everything's in order.
I dont know why, when I try it, it doesn't work, so that's why I need proofreading!

Thanks in advance!

https://www.dropbox.com/s/27vwqy24wlu37dq/Canada%20Den%20Layout.css

Hello!

I was able to get the CSS working on my den page. It could be that your browser isn't cooperating with Dropbox at the moment, and it needs to be hosted on a separate site.

Also make sure when adding the code to your den, you switch the www to dl in the Dropbox link. If you continue having issues or need any help, I'd be happy to help you further!

I use Microsoft Edge (Last Version)

<link rel="stylesheet" type="text/css" href="https://dl.dropbox.com/s/27vwqy24wlu37dq/Canada%20Den%20Layout.css">

Try adding this (make sure code view is turned on!) and see if that works, then we'll go from there!

Yay it worked! 
Thanks!