This is a really good start. I think that this game would benefit from a few more levels, and maybe some variation in art from time to time. I also think that it would be easier to control if left-click placed tiles, and right-click destroyed tiles, but that's just a suggestion. The infinite mode could also benefit from benchmarkers and some slightly more randomized patterns.

All in all, this is a good start, and with the right care, could be a really good game. Keep working on it, and see what happens!