$('map-close-button').observe('click',function (event){
    event.stop();
    $('map-popup').hide();
    $('show-google-map').show();
  });
  
  document.observe('dom:loaded', function() {
    $('show-google-map').hide();
    $('show-google-map').observe('click',function (event){
      $('map-popup').show();
      this.hide();
    });
  });