/** scroll-top **/
* {
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
}

.scroll-top.scroll-top-visible {
    opacity: 1;
}

.scroll-top {
    overflow: hidden;
    -webkit-transition: all .3s ease-in-out;
    -o-transition: all .3s ease-in-out;
    transition: all .3s ease-in-out;
    z-index: 1000;
    background-color: #555;
    color: #fff;
    bottom: 40px;
    right: 40px;
    position: fixed;
    opacity: 0;
    width: 4em;
    height: 4em;
}

.css-arrow::before,
.scroll-top.scroll-top-icon::before {
    content: '';
    position: absolute;
    -webkit-transform: translate(-50%, -50%);
    -ms-transform: translate(-50%, -50%);
    -o-transform: translate(-50%, -50%);
    transform: translate(-50%, -50%);
}

.css-arrow,
.scroll-top .scroll-top-icon {
    -webkit-transform: rotate(45deg);
    -ms-transform: rotate(45deg);
    -o-transform: rotate(45deg);
    transform: rotate(45deg);
    position: absolute;
    top: 40%;
    left: 25%;
    height: 50%;
    width: 50%;
    border-top: 4px solid snow;
    border-left: 4px solid snow;
}


::selection {
    background-color: #f33717;
    color: #fff;
}

.scroll-top:active, .scroll-top:focus, .scroll-top:hover {
    color: #ffffff;
    background-color: #f33717;
}