Hi ! I tried your game, it 's simple to understand and funny.
Just a thing I have noticed : walkers don't stop when cars have green light, so it does lot of accidents, poors giraffes :'(
I also like the graphics. :)
Your game and mine have a commun point like it's based on green light / red light, if you want to make a try and let a feedback it will be my pleasure ! :)