alignment of footer links in ul list

hi guys

i am trying to centralise my footer links, at the moment they appear to be positioned on the left within their div, im using firebug to identify the various components but i cant find the class it is pointing to

on https://www.artbyherbie.com/wptest the page links in the footer are inside a div styled by the class .footer_menu, but the nearest class i find in my themes stylesheets is .footer_menu_ul. everytime i add text-align: center; to the style sheet it has no effect on the links. im simply trying to centralise them, or even make them into a list that looks neater

or is it something to do with the ul list styles?
all help appreciated
HH