怎么把菜单定住啊

Question

<SCRIPT LANGUAGE="JavaScript">
<!--
function showMenu() 
{ 
    var obj = document.getElementById("menu"); 
    obj.style.marginLeft = "0"; 
    
} 
function Mouse() 
{ 
    var obj = document.getElementById("menu"); 
    obj.style.marginLeft = "-225px"; 
} 
function Show(){
var obj = document.getElementById("menu"); 
obj.onmouseout = "";
}//-->
</SCRIPT></asp:Content> 
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server"> 
    <div id="menu" style="background-color: #398DC5;margin-left:-225px" onmouseout = "Mouse()" onmousemove="showMenu()"> 
        <div id="menubody" class="style1"> 
            <i class="corner"> <i class="l1"> </i> <i class="l2"> </i> <i class="l3"> </i> <i class="l4"> 
            </i> </i> 
            <div class="insidecorner" > 
                <i class="corner"> <i class="l1"> </i> <i class="l2"> </i> <i class="l3"> </i> <i class="l4"> 
                </i> </i> 
                <div style="width: 200px; height: 376px; overflow-y: auto; background-color: #D9F3F0" > 
                    <asp:TreeView ID="TreeView1" runat="server" > 
                    </asp:TreeView> 
                </div> 
                <i class="corner"> <i class="l4"> </i> <i class="l3"> </i> <i class="l2"> </i> <i class="l5"> 
                </i> </i> 
            </div> 
            <i class="corner"> <i class="l4"> </i> <i class="l3"> </i> <i class="l2"> </i> <i class="l5"> 
            </i> </i> 
        </div> 
        <div style="float: right; width: 35px; height: 400px; background: white url(.\\image\\menu.gif) no-repeat; 
            background-position: left center" > 
            <input id="Checkbox1" type="checkbox"  onclick="Show()"/> </div> 
        </div> 
</asp:Content>