fixed button if footer scroll to top page

.html

<!-- to up button -->
<div class="to-up">
    <i class="fa fa-arrow-up" aria-hidden="true"></i>
</div>
<!-- end to up button -->

.js

//to up
  $(window).scroll(function(){
    if ($(this).scrollTop() >= 200) {
      $('.to-up').show();
    } else {
      $('.to-up').hide();
    }
  });
  $('.to-up').on('click', function(){
    $("html, body").animate({ scrollTop: 0 }, "slow");
    return false;
  });

.scss

//toup
  .to-up {
    position: fixed;
    width: 40px;
    height: 40px;
    line-height: 40px;
    background-color: rgba(255,255,255,.4);
    text-align: center;
    color: $blue;
    cursor: pointer;
    z-index: 10;
    right: 7px;
    bottom: 7px;
    border-radius: 50%;
    transition: background-color .2s, color .2s;
    display: none;
    &:hover, &:focus {
      color: #fff;
      background-color: rgba(37,121,191,.4);
    }
  }

.slim

/! to up button
.to-up
  i.fa.fa-arrow-up aria-hidden="true" 
/! end to up button