#button-up {
    width: 50px;
    height: 50px;
    background:transparent;
    display: flex;
    justify-content: center;
    align-items: center;
    color:gray;
    font-size: 20px;
    border-radius: 50%;
    position: fixed;
    bottom: 50px;
    right: 50px;
    cursor: pointer;
    border: 1px solid gray;
    transition: all 300ms ease;
    transform: scale(0);

}

#button-up:hover {
    transform: scale(1.1);
    border-color: rgba(0, 0, 0, 0.808)
}