Hi so my thoughts are its good you’ve tried something more challenging with a fixed background and content moving over that background.
Visually I think you sort out the fontsizes, that of the title being too large and menu rather small to click to transverse.
I tested it for mobile design i.e move resize it small, and content wasn’t flowing too well. This is where I would recommend some sort of responsive grid system like bootstrap so it the grid resizes to fit small screens.
So I would say you’ve got some good ideas, like fixed footer, fixed menu on the left and fixed background to the titles. Looking at your css I’m not sure as why you are are using vh and vw values. care to explain? You may want to check out http://learnlayout.com/ if you are not using a framework like bootstrap.
Within that link you’ll learn about the different ways of creating layouts in css, and how to make menus responsive for a small screen.