preloader

common.js

$(window).load(function() {
	$(".loader_inner").fadeOut();
	$(".loader").delay(400).fadeOut("slow");
});

index.html

<div class="loader">
  <div class="loader_inner"></div>
</div>

main.css

.loader {
  background: none repeat scroll 0 0 #ffffff;
  bottom: 0;
  height: 100%;
  left: 0;
  position: fixed;
  right: 0;
  top: 0;
  width: 100%;
  z-index: 9999;
}
.loader_inner {
  background-image: url("../images/preloader.gif");
  background-size: cover;
  background-repeat: no-repeat;
  background-position: center center;
  background-color: #fff;
  height: 60px;
  width: 60px;
  margin-top: -30px;
  margin-left: -30px;
  left: 50%;
  top: 50%;
  position: absolute;
}