#div_center { width:961px; height:32px; } 
#menunav { line-height: 32px; list-style-type: none; margin-top:0px;}
#menunav a { display: block; width: 100px; text-align:center; font-size:13px;font-weight: 800 }
#menunav a:link { color:#fff; text-decoration:none;margin:0;BACKGROUND-IMAGE: url(a5.gif);}    
#menunav a:visited {color:#fff;text-decoration:none;margin:0;BACKGROUND-IMAGE: url(a5.gif);}   
#menunav a:hover {color:#f00;text-decoration:none;BACKGROUND-IMAGE: url(a5.gif);}              

#menunav li {float: left;}                   
#menunav li a:hover{BACKGROUND-IMAGE: url(a5o.gif);}