The color of square A and B at the above image is same. If you doubt this, print the image and cut square B out and then put square B beside square A. If you have a 'Photoshop" software, also you can check this.
You cant "see" it by just looking at that pic. Copy it onto a image program and cut out the squares and then you see they're identical. I still dont get how that works though, its pretty freaky. *pokes out eyes in fury*