#back-top {
	position: fixed;
			right: 2em;
			bottom: 2em;
			z-index: 10000;
	
		}
	
#back-top a {
	
	display: block;
	
	
	/* background color transition */
	-webkit-transition: 1s;
	-moz-transition: 1s;
	transition: 1s;
	border-bottom: none;
}
/* arrow icon (span tag) */
#back-top span {
	width: 68px;
	height: 68px;
	display: block;
	margin-bottom: 7px;
	background:  url("../img/up-arrow.png") no-repeat center center;
	/* rounded corners */
	-webkit-border-radius: 0px;
	-moz-border-radius: 0px;
	border-radius: 0px;
	/* background color transition */
	-webkit-transition: 1s;
	-moz-transition: 1s;
	transition: 1s;
}
#back-top a:hover span {
	
	background:  url("../img/up-arrow-hover.png") no-repeat center center;
}