CSS: Horizontal Centered List

gistfile1.css

#centeredmenu {
   float:left;
   width:100%;
   overflow:hidden;
   position:relative;
}
#centeredmenu ul {
   clear:left;
   float:left;
   list-style:none;
   margin:0;
   padding:0;
   position:relative;
   left:50%;
   text-align:center;
}
#centeredmenu ul li {
   display:block;
   float:left;
   list-style:none;
   margin:0;
   padding:0;
   position:relative;
   right:50%;
}
#centeredmenu ul li a {
   display:block;
   padding:0 10px;
   text-decoration:none;
}