Scroll to top button

<div class="to-top"><i class="fa fa-angle-double-up"></i></div>

.to-top{
  position: fixed;
  right: 25px;
  bottom: 25px;
  width: 50px;
  height: 50px;
  border-radius: 50%;
  text-align: center;
  cursor: pointer;
  z-index: 100;
  opacity: .7;
  background-color: teal;
  color: #fff;
  transition: all 0.25s;
  display: none;
  .fa {
    font-size: 32px;
    line-height: 50px;
  }
  &:hover {
    opacity: 1;
  }
}

/*To top button*/
$('.to-top').on('click', function() {
  $('body, html').animate({ scrollTop:0 },800);
  return false;
});

$(window).scroll(function() {
  if($(this).scrollTop() > $(window).height()) {
    $('.to-top').fadeIn();
  } else {
    $('.to-top').fadeOut();
  }
});