title: Why does my popup script not work in ie9?
body: <p>I don't even know where to start to fix the problem, please any help would be appreciated greatly.
  Not sure if it is the innerHeight method or the scrollTop or something entirely different. The popup doesnt show up at all when viewed in ie9 but works fine in all other browsers and ie10 and up.</p>
  
  <pre><code>$(document).ready(function () {
      function positionLightboxImage() {
          var popup = $('.popup'),
              closeBtn = $('.closeBtn'),
              overlay = $('.bgOverlay');
          overlay.hide();
          closeBtn.live('click', function () {
              popup.fadeOut();
              overlay.fadeOut();
          });
          popup.hide();
          var top = (window.innerHeight - popup.height()) / 2 - 200;
          var left = (window.innerWidth - popup.width()) / 2;
          console.log(top, left);
          popup.css({
              'top': top + $(document).scrollTop(),
                  'left': left
          }).fadeIn();
          overlay.fadeIn();
          return false;
      }
      positionLightboxImage();
  });
  </code></pre>