.bck {
	position: fixed;
	bottom: 1rem;
	right: 1rem;
	background: rgba(0,0,0,.8);
	background:#33b5e5;
	color: #fff;
	visibility: hidden;
	width: 40px;
	height: 40px;
	line-height: 50px;
	text-align:center;
	transition-property: all;
	border-radius:15;
}

.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;}



#gotop {
    position:fixed;
    z-index:90;
    right:30px;
    bottom:31px;
    display:none;
    width:40px;
    height:40px;
    color:#fff;
    background:#33b5e5;
    line-height:40px;
    border-radius:50%;
    transition:all 0.5s;
    text-align: center;
    box-shadow: 0 2px 5px 0 rgba(0,0,0,0.16), 0 2px 10px 0 rgba(0,0,0,0.12);
}
.gotop :hover{
    /*background:#0099CC;*/
	background:#FF8000;
}