.bck {
	position: fixed;
	bottom: 0.7rem;
	right: 1rem;
	background: rgba(0,0,0,.99);
	color: #fff;
	visibility: hidden;
	width: 43px;
	height: 43px;
	line-height: 43px !important;
	text-align:center;
	transition-property: all;
	border-radius: 50px;
	box-shadow: 0 0 15px 0 rgba(0,0,0,0.9);
	z-index: 2;
}

.fa, .fab, .fal, .far, .fas{line-height: 0;}

.bck:hover{background-color: #c4191f;}

.bck.bck-on {visibility: visible;}

.fade{opacity: 0;}

.bck-on.fade{opacity: 1;}

.rightToLeft {right : -50px;}

.bck-on.rightToLeft{right: 1rem;}

.bottomToTop {bottom: -50px;}

.bck-on.bottomToTop {bottom:1rem;}

.bck-leftToRight {left: -50px;}

.bck-on.leftToRight {left:1rem;}

.topToBottom {top: -50px;}

.bck-on.topToBottom {top:1rem;}

@media (max-width:400px){
	
	.bck{bottom: 2.5rem;}
}