Can’t blame a guy for trying. 
But seriously, that theme does a bunch of stuff that gives you some ideas about what themes can do. Being able to make a whole new topic list is amazing. Cleaning it up (there is tons of code that just doesn’t belong, but when I tried to remove it I broke stuff and eventually left it rather than finding where I’d mucked up a closing parenthesis or . . . something), even just for yourself, would be a pretty good exercise. To give you more context to know if my advice is likely to be of any use to you, this is from someone with a CS degree who quit learning HTML in about 1998. I understand what CSS can do theoretically, and remain fairly completely flummoxed by Javascript and don’t understand where Javascript ends and Ember starts. I frequently try to make changes that I think will be trivial and end up breaking the world.
Good luck!