.backtotop {
  position: fixed;
  opacity: 0;
  visibility: hidden;
  -webkit-transition: opacity .3s 0s, visibility 0s 0s, background-color .3s 0s;
  transition: opacity .3s 0s, visibility 0s 0s, background-color .3s 0s;
  bottom: 15px;
  right: 15px;
  -webkit-box-shadow: 0 3px 10px rgba(0, 0, 0, 0.3);
          box-shadow: 0 3px 10px rgba(0, 0, 0, 0.3);
  background-color: #e1433c;
  background-color: rgb(164, 60, 225);
  height: 40px;
  width: 40px;
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-align: center;
      -ms-flex-align: center;
          align-items: center;
  -webkit-box-pack: center;
      -ms-flex-pack: center;
          justify-content: center;
  border-radius: 3px;
}
.backtotop img {
  width: 50%;
  height: auto;
}
.backtotop.active {
  opacity: 1;
  visibility: visible;
}
.backtotop:hover {
  background-color: #FE701B;
  background-color: #8a217c;
}