Replace Color tool. To see this tool at work, select Image -> Adjustments -> Replace Color. Apply it to a duplicate of the background layer.
Read more: http://digital-photography-school.com/changing-color-in-photoshop
Another Method:
Hidden under the default Brush tool is the Colour Replacement Brush.

Fiddling with this brush will allow finer control to replace a colour under the crosshair but within the circle.

Read more about the Colour Replacement Tool here: http://www.photoshopessentials.com/photo-editing/color-replacement-tool/
©2012 Mr. D. Sader | Communication Technology | All Rights Reserved
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I enabled the following “Advanced” Safari CSS Inspect Element trick so long ago, I forgot I had done it. Of course on my own machines, I enabled this once, and haven’t had to since. In the school MacLab though, students wanting to edit/inspect CSS will need to re-enable the Safari Develop menu each time they log in. C’est la vie.
After enabling the Develop menu, a right-click on any element of a web page should cause the Inspect Element contextual menu to appear.
There you go, infinite design possibility enabled.
©2012 Mr. D. Sader | Communication Technology | All Rights Reserved
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