javascript function is not working in asp.net

 <div>
     <style type="text/css">
  .black_overlay{
display:none;
position: absolute;
top: 0%;
left: 0%;
width: 100%;
height: 100%;
background-color:black;
z-index:1001;
-moz-opacity: 0.8;
opacity:.80;
filter: alpha(opacity=80);
}

  .popup {
    width:439px;
    height:365px;
    position:fixed;
    top:50%;
    left:36%;
    right:10%;
    bottom:50%;
    margin:-50px 0 0 -100px; /* [-(height/2)px 0 0 -(width/2)px] */
    z-index:2222;
    background-color:#FFFFFF;
     color:White;
    visibility:hidden;
  }
    .style1
    {
        height: 15px;
    }
    .style2
    {
        width: 40%;
        height: 97px;
    }
    .style3
    {
        height: 97px;
    }
</style>

<script type="text/javascript">
    
    function show_popup(pric) {
        //calling from code behind...
       
        var popup = document.getElementById('<%=popup.ClientID %>');
        popup.style.visibility = 'visible';
        document.getElementById('Div1').style.display = 'block';
        document.getElementById('<%=lblnotice.ClientID %>').innerHTML = pric;

        return false;
    }
    function hidePopup() {
        var popup = document.getElementById('<%=popup.ClientID %>');
        popup.style.visibility = 'hidden';
        document.getElementById('Div1').style.display = 'none';
        return false;
    }
</script>
<asp:DataList ID="dl" runat="server" OnItemDataBound="item_bound">
<itemtemplate>
<asp:Label ID="ru" Text='<%# DataBinder.Eval(Container.DataItem,"name")%>' runat="server">
 
                   <asp:LinkButton ID="lnkviewcart" CausesValidation="true" Enabled="true"  CommandName="imgclicked" Visible="false" runat="server"  Text="See Price in Cart" >
</itemtemplate>

  <div id="Div1" class="black_overlay">
                  </div>
                  <div id="popup" align="center" class="popup"  runat="server">
                    
  <table width="100%" style="removed50%;">
  <tr><td><hr style=" height:10px; background-color:#ff0000;" /></td></tr>
  <tr align="center" style="  width:90%;"><td align="left" style=" color:#565454;"><table width="100%"><tr><td style="font-family:Verdana; font-size:16px; color:#565454; ">Your Price @ Lee's Tools</td> 
  <td><asp:Label ID="lblnotice" runat="server" ForeColor="#ff0000" Font-Names="Verdana" Font-Size="15px" Font-Bold="true"></td></tr></table></td></tr>
  <tr><td><hr style=" height:4px; background-color:#ff0000;" /></td></tr>

  <tr><td></td></tr>

   <tr>
   <td align="right">
   <table width="100%">
   <tr><td align="left"><asp:ImageButton ID="imgclose" runat="server" ImageUrl="../Image/closebut.png" OnClientClick="return hidePopup();" /> </td>
   <td align="right"><asp:ImageButton ID="imgpopadd" runat="server" ImageUrl="../Image/Addtocart/cart_button.png" OnClick="addtocart_clicked_popup" /> </td>
   </tr>
   </table>
   </td></tr>
   <tr><td></td></tr>
  </table>
 
</div>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;

namespace popjavascript
{
    public partial class WebForm1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!Page.IsPostBack)
            {
                Bind();
            }

        }

        public void Bind()
        {
            DataTable dt = new DataTable("new");
            dt.Columns.Add("name");
            dt.Columns.Add("price");
            dt.Rows.Add("christh", "100.00");


            //  dt.Rows.Add("100.00","price");
            dl.DataSource = dt;
            dl.DataBind();
        }
        protected void addtocart_clicked_popup(object sender, ImageClickEventArgs e)
        {

            Response.Write("hello");
        }

        protected void item_bound(object sender, DataListItemEventArgs e)
        {
            LinkButton linkmp = (LinkButton)e.Item.FindControl("lnkviewcart");
            Label lblprice = (Label)e.Item.FindControl("ru");
          
            linkmp.Visible = true;
            linkmp.OnClientClick = "retun show_popup(' " + lblprice.ToString().Trim() + "'); retun false;";

        }
    }
}