#back-top{
    position: fixed;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    line-height: 30px;
    bottom: 80px;
    right: 10px;
    display: none;
    cursor: pointer;
    z-index: 999;
    background: #000;
    text-align: center;
    font-size: 30px;
    color: #FFF;
    transition: all 0.5s ease;
}
#back-top a{
	color: #fff;
}