title: Jquery - Change Background position on 1st click, reset on the 2nd
body: <p>Evening all! I have half a script that I need to change the CSS background position of an element when it is clicked - this works fine. However I need the CSS to reset the background position to 0 0 on the 2nd click;</p>
  
  <p>Help much appreciated!</p>
  
  <pre><code>$(document).ready(function(){
  $('#login-btn').click(function(){
                  $('#login-btn').css('backgroundPosition', '0px -39px');
                   }, function(){
                  $('$login-btn').css('backgroundPosition', '0px 0px');
  
               });
              });
  </code></pre>