I was able to beat the first two levels with all diamonds, but I had some difficulty with the third level. Wasn’t able to beat it, but I think you had a good game loop.
One piece of feedback I would have is that it felt like the slide activation was slightly delayed from when I pressed the button by like a quarter of a second. It was enough that it made the first diamond of level one a little tricky to get right (kept getting caught on the metal crossbar above it).
Nice work!