Interesting style and excellent ambience, but I think the platforming really falls flat. The controls are good, but a lot of it (including the beginning) is just time filler. No stakes, no interesting mechanics, just jumping through tunnels, then up towers, and by the time you're at the more interesting stuff it's basically over.
You certainly achieved what you set out to do, but I think there could be so much more to this. Adding some variety to the platforming, as well as checkpoints (perhaps in the form of a level select) would make this much more fun.
Extra note: Add controls for Arrow Keys as well?
I hope you revisit this and innovate on it a little bit more.