Getting Rid of Active Tab's Bottom Border?

I've been trying to find a solution to removing the bottom border on the active tab. Is it possible that because it doesn't validate as XHTML Strict that it won't work or is it a problem in the CSS? I've searched through the issue list and found http://drupal.org/node/547586 but it doesn't really answer my question.

site: http://www.library.uni.edu/business-portal

css:

// FROM LIBRARY.CSS (Main Stylesheet) //

/* Quicktabs-5 business portal */
#quicktabs-5
  {
    width: 95%;
	  }
	#quicktabs_container_5 { height: 100%; }
#quicktabs-5 td,
#quicktabs-5 tr,
#quicktabs-5 table
{ border: 1px solid #000;}

/***********************************************/

//FROM QUICKTABS.CSS//

div.quicktabs_tabpage.nojs-hide {
  display: none;
}

ul.quicktabs_tabs {
  margin-top: 0;
}
ul.quicktabs_tabs li {
  display: inline;
  background: none;
  list-style-type: none;
  padding: 2px;
}
ul.quicktabs_tabs li a:focus {
  outline: none;
}

/***********************************************/

//FROM QUICKTABS/BASIC.CSS//

.quicktabs_main.quicktabs-style-basic{
  background-color:#fff;
  border:1px solid #aaa;
  border-top:none;
  padding:10px;
  clear:both;
}
ul.quicktabs_tabs.quicktabs-style-basic{
  border-bottom:1px solid #aaa;
  padding:0 5px 0 0;
  font:bold 12px/19px Verdana !important;
  font-weight:bold;
  height:19px;
  margin:0;
}
ul.quicktabs_tabs.quicktabs-style-basic a{
  font:bold 12px/19px Verdana !important;
  text-decoration:none;
  color:#aaa;
}
ul.quicktabs_tabs.quicktabs-style-basic a:hover{
  color:#555  !important;
}
ul.quicktabs_tabs.quicktabs-style-basic li{
  border:1px solid #e5e5e5;
  border-bottom:none;
  padding:2px 5px;
  margin:0 3px 0 0;
  position:relative;
}
ul.quicktabs_tabs.quicktabs-style-basic li:hover{
  border:1px solid #ccc;
  border-bottom:none;
}
ul.quicktabs_tabs.quicktabs-style-basic li.active{
  border:1px solid #aaa;
  border-bottom:1px solid #fff;
  background-color:#fff;
}
ul.quicktabs_tabs.quicktabs-style-basic li.active a{
  color:#027AC6;
}

Thank you for your time and any comments are welcome!