It works on Opera, but:
1) Controls are really awkward.
2) Bright white of the blocks not only hurts your eyes but also makes it difficult to see their sizes/shapes.
3) There's no way to see which level you're on.
Why it doesn't save my progress automatically?? After completing main levels it glitched and the menu for challenge levels was blank. So I reloaded the page, and - surpriiise! - all my progress is lost! Well, I guess I won't ever get hard badge=P
I was stuck for a while until I realised that you can actually go to the left from your living room and get to the kitchen! I wish it wasn't so subtle.