#backToTopBtn {
    display: none;
    position: fixed;
    bottom: 20px;
    right: 0px;
    z-index: 999;
    font-size: 20px;
    border: none;
    outline: none;
    background-color: rgba(105, 105, 105, 0.4);
    color: white;
    cursor: pointer;
    padding : 3px 15px 3px 15px;
    border-radius: 7px;
  }
  
  #backToTopBtn:hover {
    background-color: rgba(197, 197, 197, 0.5);
  }