Developing a "HTML5" game is a very great experience. The only HTML you need though is <!DOCTYPE html><meta charset="utf8"><canvas></canvas><script> ... </script> The rest is just JavaScript and interaction with the canvas. And writing a server in NodeJS is almost trivial if you already know JavaScript. I recommend not using a game engine or framework! And as a general advice, actually don't do much abstraction at all! In-line all functions within the animation/render/game loop. Your next weekend project should be a ".io" game, it's a lot of fun!
