#pagetop {
  position: fixed;
  right: 10px;
  bottom: 20px;
  margin: 0;
  z-index: 9999;
}
#pagetop a {
  position: relative;
  display: flex;
  width: 60px;
  height: 60px;
  justify-content: center;
  background: rgba(0, 0, 0, 0.8);
  transition: opacity 0.6s ease;
  color: #fff;
  align-items: center;
  text-decoration: none;
  font-size: 14px;
}
#pagetop a:hover {
  opacity: 0.3;
}
@media screen and (max-width: 767px) {
  #pagetop a {
    width: 50px;
    height: 50px;
  }
}