#nav {padding:0; margin:0; list-style:none; height:80px; position:relative; z-index:500;}
#nav li.top {display:block; float:left;}
#nav li a.top_link {display:block; float:left; height:80px; line-height:80px; color:#333; text-decoration:none; font-size:18px; padding:0px; cursor:pointer; font-weight:500}
#nav li a.top_link span {float:right; display:block; padding:0 12px 0 12px; height:80px;font-family:Microsoft YaHei;}
#nav li a.top_link:hover {color:#00409a; height:80px}
#nav li a.top_link:hover span {background:url(blank_over.gif) no-repeat right top;}
#nav li a.top_link:hover span.down {background:url(blank_overa.gif) no-repeat right top;}

/* Default list styling */

#nav li:hover {position:relative; z-index:200;}

/* keep the 'next' level invisible by placing it off screen. */
#nav ul, 
#nav li:hover ul ul,
#nav li:hover ul li:hover ul ul,
#nav li:hover ul li:hover ul li:hover ul ul,
#nav li:hover ul li:hover ul li:hover ul li:hover ul ul
{position:absolute; left:-9999px; top:-9999px; margin:0px; padding:0px; list-style:none; display:block; width:160px}

#nav li:hover ul.sub
{left:0; top:60px; background: #00409a;white-space:nowrap; height:auto; z-index:300;filter:alpha(opacity=80);-moz-opacity:0.80;opacity:0.80; z-index:700; text-align:left; display:block; padding:5px; margin:0px; width:140px;word-break:break-all} 


#nav li:hover ul.sub li
{display:block; width:100%; height:36px; position:relative; float:left;white-space:nowrap}
#nav li:hover ul.sub li a
{display:block; height:36px; width:100%; color:#fff; text-decoration:none;font-size:15px; line-height:36px; text-indent:10px}
#nav li:hover ul.sub li a:hover 
{background:#000; color:#fff; width:100%;z-index:800;filter:alpha(opacity=100);-moz-opacity:1;opacity:1;height:36px}