It took me a minute to get it, as at first I just kept jumping off into space haha but once I got into it I really enjoyed it. I like the art style and I think this is a cool concept.
My only feedback would be that as someone who found it quite challenging, you have to wait quite a long time to restart (for the text to appear then the menu to come back on) and while I was starting out, I'd like to be able to just spam starting again.
Maybe if you were to develop it further in future, something like a training zone where you can just have a go at walking and jumping around, and any time you go off into deep space, you can just press 'r' to reset. As once I'd done a bit of practice it was better but it felt hard to get to a point where I knew what to do.
Good job and nice game!