.scrollToTopBtn {
    background-color: rgba(0, 0, 0, 0);
    color: #31afd8;
    border: none;
    color: white;
    cursor: pointer;
    font-size: 18px;
    line-height: 48px;
    width: 48px;
    border-radius: 50%;
  
    /* place it at the bottom right corner */
    position: fixed;
    bottom: 30%;
    right: 20px;
    /* keep it at the top of everything else */
    z-index: 100;
    /* hide with opacity */
    opacity: 0;
    /* also add a translate effect */
    transform: translateY(100px);
    /* and a transition */
    transition: all 0.5s ease;
  }
  
  .showBtn {
    opacity: 1;
    transform: translateY(0);
  }