Idea is interesting. For 2D platformer is not so bad.
But!
1. If I reload the page, I will start all from beginning, I think this is not so handy.
2. The controls is not so good like can be. Some times I can't hit 2 buttons in one time.
3. Exit button. Why you need this? If it does not work, and you do not save progress?
4. Why blink blocks kill the Giraffe?
5. Why I need hit on the red button only with crates?
P.S. Need to work on this game, to be more better. First of all, I think better if you will make some descriptions, like on first level. For levels with enemies, crates and blink blocks. Second it will be list of levels and saving the progress.
 "Giraffe"){kind=icon}