If anyone is having a hard time believing this, try the following (for Windows users):
1) Right click on the image and select Copy Image
2) Go to your start button, select Run, and enter MSPAINT
3) When you are in Paint, type Ctrl+V to paste the image
4) There is bunch of boxes representing "tools" on the left of the screen. Click on the one in the upper right - which looks like a dotted rectangel
5) Now outline a little square in the A block, and drag it into the white part of the margin
6) Do the same for a piece of th B block
7) Yep, same color