Trés L.

It looks like I've resolved this. I changes the width and max-width settings for navbar3_logo class, and everything appears to be working properly. What clued me into that was giving the image a background color, publishing, and reloading the site to see the background color extend all the way to the right off the screen.

Update: Something messed up overnight which led me to delete all the navigation class items and rebuild the navbar, but the issue still remains.