function openPopup(url) {
   open(url, "popup", "toolbar=no,location=no,menubar=no,width=700,height=500,resizable=yes,top=0,left=0,scrollbars=yes");
 }

 function openPopupLB(url) {
   open(url, "popup", "toolbar=no,location=no,menubar=no,width=650,height=320,resizable=yes,top=0,left=0,scrollbars=yes");
 }
 
function clear_textbox()
{
if (document.getElementById('ctl00_txtemail').value  == "Your e-mail")
    document.getElementById('ctl00_txtemail').value = "";
    document.getElementById('ctl00_txtemail').style.color ="#000000";

}