"Make" Theme – Editing CSS & Creating Borders

Hi all,

I’m currently working with Make Theme. I’d like to add a border or line to separate my right-hand sidebar from my main column. I’m new to CSS so I’m not sure exactly how to do this.

You can see my website at https://www.somesundrytales.com to get the idea.

In my Dashboard under the “Appearance” tab there is an “Editor” and an “Edit CSS” Tab. The “Edit CSS” tab is a CSS Stylesheet Editor. I’m assuming I use the “Edit CSS” and not the “Editor”?

Any help you can give me would be greatly appreciated!