This is one of the basic puzzles, press one of the tiles to invert it and the tiles around it. The objective is to follow the pattern at the down-left corner, repeat until there are no more patterns to follow to win. You can turn on the music by clicking the music icon and turn it off by clicking the music icon again, obviously (-._.-). Can you beat it with less time and clicks?
Credits (Costume) Music Icon by Iconfinder (Sound) Supernova by Xtrullor (Smiley) (-._.-) by @SoapFish