The background color of the original Google plus site is too bright. This extension makes it comfortable.
By this very simple extension, you can change background color of Google plus site.
In default, the color is #66cdaa (or mediumaquamarine). To change the color, move your mouse on the area marked in red in the screenshot, and set the color code into the box.
(FYI) color reference:
2012-04-13: Added font color feature. You can darken/lighten font colors of G+ text.
My G+ account is: https://plus.google.com/109370984101702523623