.scroll-to-top-button {
  background: #263238;
  display: block;
  width: 50px;
  height: 50px;
  -webkit-box-shadow: 0 0 10px 0 rgba(38, 50, 56, 0.5);
          box-shadow: 0 0 10px 0 rgba(38, 50, 56, 0.5);
  border-radius: 50%;
  -webkit-transition: all .25s ease-in-out, bottom .7s ease-in-out;
  transition: all .25s ease-in-out, bottom .7s ease-in-out;
  opacity: .3;
  color: #FFF;
  font-size: 2rem;
  line-height: 48px;
  text-align: center;
  text-decoration: none;
  cursor: pointer;
  position: fixed;
  right: 2rem;
  bottom: -200px;
  z-index: 800;
}

.scroll-to-top-button.active {
  bottom: 50px;
}

.scroll-to-top-button:hover {
  background: #263238;
  color: #FFF;
  opacity: 1;
}