The idea is SUPER!!! I really like it, I really love unconventional ideas for levels. But in my opinion there is one big drawback - poor visibility. It seems to me that the window could have been made larger and then it would have been better visible and the gameplay could have been made a little longer. Although for such a short gameplay I would still give it a 5 if the visibility were improved. For this reason I will give it a 4. But the idea is SUPERB! I love. Well done!