Add this to additional.css template. You can only do it via CSS if you do NOT have Profile Customization turned on.
HTML Code:
#member_content #sidebar_container a {color: green;} /* left link color */
#member_content dl.tabslight dd.userprof_moduleinactive a {color: red;} /* inactive tab font color */
#member_content dl.tabslight dd.userprof_moduleinactive {background: black;} /* inactive tab background color */
#message_form div.userprof_headers {background: pink;} /* around VM message area */
#sidebar_container .underblock {background-color:pink;} /* not sure about this one - bar color */
div.group .userprof_button {background: green; color: orange;} /* VM editor buttons */