Rated 5 out of 5 stars

I actually created two versions of alternative - and + buttons, and saved them as 32-bit PNG images with transparent backgrounds. I uploaded them here and you are free to use them as needed. I extended the - and + by 1 pixel to make up for the absence of the green circles, and also added semi-transparent grey border for a more natural softer effect.

http://i.imgur.com/6PoBiXY.png

http://i.imgur.com/07E4i7h.png

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