*{margin:0;padding:0;border:0;}
#top {
line-height: 43px; list-style-type: none;
}
#top a {
display: block; width: 90px; text-align:center;
}
#top a:link {
color:#FFFFFF; text-decoration:none;
}
#top a:visited {
color:#FFFFFF;text-decoration:none;
}
#top a:hover {
color:#FFFFFF;text-decoration:underline;
}
#top li {
float: left;
}
#top li a:hover{
width: 90px;height: 43px;
background-image:    url(http://www.yaosing.com/images/nav-over.gif);
background-repeat: no-repeat;
}