@media (min-width: 769px) { /* PC用 */
  #page-top {
    font-size: 14px;
    display: block;
    position: fixed;
    z-index: 9999;
    bottom: -80px;
    right: 10px;
    width: 60px;
    padding: 10px 10px;
    background: #385071;
    color: #fff;
    text-align: center;
    text-decoration: none;
    transition: .5s;
  }
  #page-top:hover {
    background-color: #60728b;
  }
}
@media (max-width: 768px) { /* SP用 */
  .page-top {
    font-size: small;
    display: block;
    position: fixed;
    z-index: 9999;
    bottom: -60px;
    right: 10px;
    width: 80px;
    padding: 20px 10px;
    background: #385071;
    color: #fff;
    text-align: center;
    text-decoration: none;
    transition: .5s;
  }
  .page-top:hover {
    background-color: #60728b;
  }
}