Changing Color of text within buttons

Hello,

I just bought Community Answers and wanted to adapt the theme. Everything works fine so far except changing the color of the text for the buttons e.g. "continue". On my test page:

http://www.motorsportfreunde-ludwigshafen.de/index.php?option=com_communityanswers&view=answers&Itemid=144

the colour of the text is orange but t ned to be white. Could you pleas help me?

Thanks for your support,

Horst