How to create a persistent/sticky vertical navigation, left side of screen?

We would like our community to look and feel a bit more like an app, with quick links to the 5 main community groups that we offer. We want users to be one click away from these core community spaces and their unique offerings, no matter where they are in the community. (I do recognize that we could have a traditional top nav that is persistent, but it's too subtle and as such is often blends in with the UX.)

I've hacked together a left nav which lays OVER TOP of our Telligent site. I did this by using an html tile widget loaded with the needed HTML/CSS code. Here's what I've got (see video) and it looks/functions almost as expected, on a nice full sized screen. But because it's laying OVER the community page, instead of shifting the community to the right, the bar takes up too much real estate and on smaller/scaled screens, it overlays, thus conflicting with the main content of the screen.