Javascript pop-up Div layer with closed

<SCRIPT type = "text/JavaScript" Language = "JavaScript">
Function show (checkbox_list ){
VaR checkbox_list = Document. getelementbyid (checkbox_list );
Checkbox_list.style.display = "Block ";
}
Function hidden (checkbox_list ){
VaR checkbox_list = Document. getelementbyid (checkbox_list );
Checkbox_list.style.display = "NONE ";
}
</SCRIPT>

<Table width = "100%" border = "0" cellpadding = "0" cellspacing = "1" class = "table">

<Tr>
<TD colspan = "7" style = "position: relative;">
<Input name = "B2" type = "button" value = "" class = "button" onclick = "show ('checkbox _ sizemodellist ')"/>
<! -- Div begin -->
<Div id = "checkbox_sizemodellist" style = "display: none; Z-index: 2000; position: absolute; left: 3px; top: 23px; Border: 1px solid # 06c; padding: 0px; Background: # FFF; ">
<Div style = "Background: # 0184de; text-align: Right; padding-Right: 3px;"> <span style = "width: 12; border-width: 0px; color: White; font-family: webdings; cursor: hand; left:-200; "onclick =" hidden ('checkbox _ sizemodellist ') "> r </span> </div>
<Asp: placeholder id = "PHL" runat = "server"> </ASP: placeholder>
& Nbsp; <input name = "" type = "button" class = "button" style = "width: 40px; "value =" Submit "/> & nbsp; <input name =" "class =" button "type =" button "onclick =" hidden ('checkbox _ sizemodellist ') "value =" close "style =" width: 40px; "/> <br/>
</Div>
<! -- Div end -->
</TD>
</Tr>
</Table>