As promised, although a little late I have updated the Regex to get CSS classnames via C#. The problem I had was that it would find file extensions in a url specified by the "url(xyz.png)" in an attribute.
I added a little negative look behind and now it seems to work prety well:string css = @".someclass{background: white url(someimage.png) repeat-x top left;}.someclass2{background: white url ( someimage.png) repeat-x top left;}";MatchCollection arr = Regex.Matches(css, @"(?<!url\s*(.)(.[-]?[_a-zA-Z][_a-zA-Z0-9-]|[^\0-\177]\[0-9a-f]{1,6}(\r\n[ \n\r\t\f])?|\[^\n\r\f0-9a-f])");string class1 = arr[0].Value;string class2 = arr[1].Value;I lead the Chrome Developer Relations team at Google.
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