I feel like you had a really great difficulty curve going, I'd love to see more when you're not a time crunch!
Music is a great vibe. I noticed the parallax scrolling in level 3, and when I turned around to see it again I got a good smile out of the 'I was here' I can see a lot of polish in this, but a few pieces of feedback I have:
I accidentally noticed you could pick up two at a time in the level with the two horizontal scalers and that's really great quality of life. However it's easy to bump another platform you're standing on and it becomes selected, and then you fall through. Maybe have a second input to confirm selecting another if you continue with the game? Maybe right click.
The last level gave me a lot of trouble, but I could see it being intentional. It didn't even occur to me to try running through the platform I thought I had to jump over it.
Once I did figure it out though, I accidentally kept bumping the second platform on the one I was standing on and falling through :)
Really great submission!