.back-to-top {
  position: fixed;
  bottom: 2em;
  right: 2em;
  text-decoration: none;
  color: #000000;
  background-color: rgba(255, 255, 255, 0.6);
  font-size: 12px;
  font-weight: bold;
  padding: 1em 2em;
  display: none;
  z-index: 10000;
  border-radius: 50px;
  -moz-border-radius: 50px;
  -webkit-border-radius: 50px;
  -ie-border-radius: 50px;
  -o-border-radius: 50px;
}