#return-to-top {
    position: fixed;
    bottom: 70px;
    left: 15px;
    background: rgba(143, 143, 143, 0.31);
    width: 47px;
    height: 47px;
    display: block;
    text-decoration: none;
    -webkit-border-radius: 35px;
    -moz-border-radius: 35px;
    border-radius: 35px;
    display: none;
    -webkit-transition: all 0.3s linear;
    -moz-transition: all 0.3s ease;
    -ms-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
    z-index: 9999;
}
#return-to-top i {
    color: #fff;
    margin: 0;
    position: relative;
    left: 15px;
    top: 9px;
    font-size: 27px;
    -webkit-transition: all 0.3s ease;
    -moz-transition: all 0.3s ease;
    -ms-transition: all 0.3s ease;
    -o-transition: all 0.3s ease;
    transition: all 0.3s ease;
}
#return-to-top:hover {
    background: #f87907;
}
#return-to-top:hover i {
    color: #fff;
    top: 8px;
}