Perfectly centered tabs, cross-browser, no-hacks, no inline-block

/*
Technique by Matthew James Taylor
http://matthewjamestaylor.com/blog/beautiful-css-centered-menus-no-hacks-full-cross-browser-support
 
Corresponding markup:
 
<div id="centeredmenu">
   <ul>
      <li><a href="#">Tab one</a></li>
      <li><a href="#" class="active">Tab two</a></li>
      <li><a href="#">Tab three</a></li>
      <li><a href="#">Tab four</a></li>
   </ul>
</div>
 
*/
 
#centeredmenu {
   float:left;
   width:100%;
   background:#fff;
   border-bottom:4px solid #000;
   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;
   margin:0 0 0 1px;
   padding:3px 10px;
   background:#ddd;
   color:#000;
   text-decoration:none;
   line-height:1.3em;
}
#centeredmenu ul li a:hover {
   background:#369;
   color:#fff;
}
#centeredmenu ul li a.active,
#centeredmenu ul li a.active:hover {
   color:#fff;
   background:#000;
   font-weight:bold;
}