.contenido {
	width:500px;
	margin:20px auto;
	text-align: justify;
}


.ir-arriba {
	padding:20px;
	display:inline-block;
	background:#024959;
	color:#fff;
	position: fixed;
	font-size:20px;
	bottom:20px;
	right:20px;
	display:none;
	cursor:pointer;
}