How do I select the last child of a div with only a certain name using only CSS?

I have been using the following CSS to apply an effect at the bottom of elements in a menu:

.leftMenuProductWrapper div:last-child{margin-bottom:20px;}

This works fine initially, however after adding more elements in the menu, I realized it was a problem. I really only want to select the last div with .leftMenuProductButton within .leftMenuProductWrapper

Anyw开发者_StackOverflow中文版ay to do this without using Jquery, just pure CSS?

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Sounds like http://reference.sitepoint.com/css/pseudoclass-nthlastchild

Might want to check your browser compatibility though.