this is why i asked for a link.
i cannot tell you what page to edit unless i see your site.
the page to edit will be different depending on the theme you are using in power store.
this is also why i suggested using fir bug, you can use fire bug to help you determine what css file edit, it is the tool i will end up using.
at any rate, i need a link to your site to determine the page that needs to be edited.