#back-top a {
    position: fixed;
    bottom: 20px;
    right: 25px;
    background-color: #182b3e;
    width: 55px;
    height: 55px;
    text-align: center;
    font-size: 25px;
    z-index: 100;
    color: white;
    transition: all .5s ease-in-out;
}

#back-top a:hover{
    background-color: #03203e;
}

#back-top i{
    font-size: 35px;
    padding-top: 8px;
}