#myBtn {
display: none;
    position: fixed;
    bottom: 0px;
    right: 0px;
    z-index: 99;
    font-size: 15px;
    border: none;
    outline: none;
    /* background-color: #b7b5b5; */
    color: white;
    cursor: pointer;
    padding: 2px;
    border-radius: 4px;
    width: 40px;
    height: 30px;
}

#myBtn:hover {
  /* background-color: #555; */
}