如何在Flash上​​重叠html元素

<table>
<tr>
    <td> <ul class=\"nav\">
                <li>Menu</li>
                <li>Menu</li>
                <li>Menu</li>
                    <ul>
                        <li>Sub Menu</li>
                        <li>Sub Menu</li>
                        <li>Sub Menu</li>
                    </ul>
        </ul>
    </td>
    <td> <div class=\"flash\">Flash</div> </td>
</tr>
</table>

.nav li ul{
    postion:absolute;
    z-index:+9999;

}

.flash{
    height:900px;
    width:600px;
    position:relative;
    z-index:-999999;
}