Quite good! I was initially questioning the duality of space invaders and breakout but it worked quite well. However I do think it would be a bit better if either there was only one ball (during breakout mode) or the balls were somehow programmed so that they would reach the edges at the same x position or at different times because sometimes it was impossible to avoid losing a life. Also I think it might be better if switching "modes" was on a timer rather than based on score because when you get to only one or two blocks left it becomes very unlikely for one of the balls to hit them. Another more minor thing is that it would be nice if we could have some visual indication of where the blocks will start moving in the other direction, as it is very difficult to tell and makes it hard to line up shots. Also the sound effects are a bit loud compared to the music imo but that might just be personal preference.
Overall quite fun, definitely original and a lot better than I could do in 48 hours lol
Good stuff!