Good job figuring out how to make a game work in 1D. Definitely a hard design challenge. I like your music track. Your game is definitely more legible than mine, which is important for these 1D games. I also enjoyed how the instruction text gradually appeared as you progressed, functioning as something of a tutorial.
I think the game might benefit from a bit more variety. The challenges pretty much boil down to keep pace between two moving red spots or move between blinking red spots, relying on memory to for exactly where they'll be when they show up again. Perhaps you could have a small teleport/dash to let you get past small red spots or maybe there could be an exploration element of some sort or maybe you could add some story to your simple premise to contextualize things, a la Thomas Was Alone.