css / color issue

Hi,
It seems the buttons may not have their css color set firmly.
My posts have green link css so it causes the buttons to also be green.
How should I set the css for the buttons to be white?

This seems like maybe a bug/loophole as I was thinking the buttons would have their own css which wouldn’t accidentally get overridden by a theme.

Thanks in advance for the help.

The page I need help with: [log in to see the link]