It may be hard to believe, but the two 'marked' squares (marked with small white dots) are the SAME shade of blue! We know that one 'looks' darker than the other, but it isn't. In order to help you see this, we've provided a "negative image" button. Click on the button to reverse all the colors in the image. White becomes black, green becomes purple, blue becomes orange, etc. In the negative image, it's easier to see that the marked squares are in fact the same shade. Now is this illusion keeeeewl or what?!

 

               

 
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