preloader

gistfile1.txt

jQuery(window).on('load', function () {
	var $preloader = jQuery('#page-preloader'),
			$spinner   = $preloader.find('.spinner');
	$spinner.fadeOut();
	$preloader.delay(350).fadeOut('slow');
});

/* insert in the beggining of body or somewhere else */
<div id="page-preloader"><span class="spinner"></span></div>

#page-preloader {
  position: fixed;
  left: 0;
  top: 0;
  right: 0;
  bottom: 0;
  background: #fff;
  z-index: 100500;
}

#page-preloader .spinner {
  width: 32px;
  height: 32px;
  position: absolute;
  left: 50%;
  top: 50%;
  background: url('../img/spinner.gif') no-repeat;
  background-size: cover;
  margin: -16px 0 0 -16px;
}