A quick comment on UX - my laptop is old (see: the aforementioned ancient processor), and these types of menus are extremely inefficient for screen real-estate. On a 1366x768 display, most modern webapps/applications simply need that full screen real estate. They become unusable if you try to split in either direction (which I want to do oh so often, using a tiling window manager). Even when given the full screen resolution, some things are simply unusable.
I think a design like this is at risk of falling into the "always unusable" category for hardware like mine. Of course, I know this is just a demo, and context matters a lot, but I still think it's something worth considering.
If each menu item is 65px in height - on a 1366x768 display, once you account for taskbars, titlebars, browser tab interfaces, menu bars, etc, you'd probably be lucky to have about 500px of vertical real estate left for the main content. So you'd barely be able to shove ~7.5 elements on screen with a list like this. Just food for thought.