Not bad, its fun and the controls are responsive, the tags bother me because I'm not sure if the early 2000's are considered "retro"
A little something: There are plenty of games that cannot be played by the colorblind, like a lot of match 3 games, or perhaps this. That's just the way it is, since color is one of the most common ways to give a signal. If you're colorblind to some extent, that means that there are some games that will become harder to play, because that's part of your handicap. People who are completely blind cannot play most games, and not every game needs to be accessible to the blind. Same thing goes for colorblind.
As for the game, I found it pretty fun, even if it is a bit easy. Sometimes, it's best to relax, and just play to win and watch a number increase. Even still, I got bored by level 15.
An autosave feature every time you beat a level would be a great feature.
Just a quick heads up, something you may want to consider that should be fairly easy to fix. This game is not good for those (like me) who are red-green colour blind! The spikes are too small and at a glance to red-green colour blinds look just like the grass. I died a few times and had no idea it was because I landed on spikes!