inputpassworddecrypt.html

<html>
<form id='myForm' style="font-family:Georgia;">

<table>
<tr><td><h2>Enter your Password</h2></td></tr>
<tr><td><input name='password' type='password' value="" ></td></tr>
<tr><td><div id="submitbuttcontainer"><img id="submitloader" style="display:none;" src='https://lh6.googleusercontent.com/-S87nMBe6KWE/TuB9dR48F0I/AAAAAAAAByQ/0Z96LirzDqg/s27/load.gif' /><input id="submitbutt" type='button' onclick='showWorking();google.script.run.withSuccessHandler(onSuccess).decodeForRequest(document.getElementById("myForm"));' name="Submit" value="Submit"></div></td></tr>
</table>

</form>
<script>
function onSuccess(obj) {
  document.getElementById('submitbutt').style.display="block";
  document.getElementById('submitloader').style.display="none";
  if(obj.status == 'success') {
    alert("success");
    google.script.host.closeDialog();
   }
   else {
    alert("Incorrect Password. Please retry");
   }
}
function showWorking() {
  document.getElementById('submitbutt').style.display="none";
  document.getElementById('submitloader').style.display="block";
}
</script>
</html>