ul#topnav {position: relative;z-index:10000;}
ul#topnav li {float: left; position:relative;text-align:center;}
ul#topnav li:hover{background: #077a5b;}

ul#topnav li a {display:block;color:#ffffff;}
ul#topnav li a:hover {color: #ffffff}
ul#topnav li .sub {
    position: absolute;  
    top: 50px; 
    left: 0;
    background:#ffffff;
    float:left;
    /*--Bottom right rounded corner--*/
    -moz-border-radius-bottomright: 5px;
    -khtml-border-radius-bottomright: 5px;
    -webkit-border-bottom-right-radius: 5px;
    /*--Bottom left rounded corner--*/
    -moz-border-radius-bottomleft: 5px;
    -khtml-border-radius-bottomleft: 5px;
    -webkit-border-bottom-left-radius: 5px;
    display: none;
    z-index: 9999;
}
ul#topnav li .sub dl{
    z-index: 9999;
    position: absolute;
    background:#99CC99;
    /* older safari/Chrome browsers */
    -webkit-opacity: 0.9;
    /* Netscape and Older than Firefox 0.9 */
    -moz-opacity: 0.9;
    /* Safari 1.x (pre WebKit!) 老式khtml内核的Safari浏览器*/
    -khtml-opacity: 0.9;
    /* IE9 + etc...modern browsers */
    opacity: .9;
    /* IE 4-9 */
    filter:alpha(opacity=90);
    /*This works in IE 8 & 9 too*/
    -ms-filter:"progid:DXImageTransform.Microsoft.Alpha(Opacity=90)";
    /*IE4-IE9*/
    filter:progid:DXImageTransform.Microsoft.Alpha(Opacity=90);
}

ul#topnav .sub dl dd a {padding: 0 8px;color:#333333;line-height:42px;width: 133px;}
ul#topnav .sub dl dd a:hover {
    color:#ffffff;
    background:#039268;
}