#backtotop { 
	height:auto;
	position:fixed;
	right:30px;
	bottom:40px;
	display:none;
	z-index:30;
	display: block;
	opacity: 0.6;
}

#backtotop ul {
	padding:15px 0px;
	list-style-type: none;
}

#backtotop ul li a {
	background:url(../img/up.png) center top no-repeat;
	background-size: 48px 48px;
	display: block;
	width: 48px; height: 48px; float: right;
	right: 10px;
	text-indent: -9000px;
}
	
#backtotop ul li a:hover {
	height:58px;
}