JSFiddle - React, Tailwind, and code Playground

HTML

<div class="caldera-forms-modal">
  [caldera_form_modal id="CF5adb0684df741" type="button" width="500"]<i class="x-icon x-icon-envelope" data-x-icon="" style="font-size:20px">　문의하기</i>[/caldera_form_modal]
</div>
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<div...

CSS

.caldera-forms-modal {
  color: white;
  background-color: #d65b5b;
  border: 1px solid #d65b5b;
  border-radius: 5px 0px 0px 5px;
  height: 40px;
  width: 150px;
   !imporatnt;
  position: fixed;
  z-index: 9999;
  float: right;
  right: -104px;
  bottom: 2%;
  transition: right 0.3s;
  transition: opacity 1s ease;
  opacity: 0.5;
  filter: alpha(opacity=50);
}

.caldera-forms-modal:hover {
  right: 0%;
  opacity: 1.0;
  filter: alpha(opacity=100);
}

.caldera-forms-modal.nav-up {
  opacity: 1;
}

.caldera-forms-modal.nav-down {
  opacity: 0;
}

/** end **/

JavaScript

(function($) {
  var lastScrollTop = 0;
  $(window).scroll(function(event) {
    var st = $(this).scrollTop();
    if (st > lastScrollTop) {
      $('.caldera-forms-modal').removeClass('nav-down').addClass('nav-up');
    } else {
      $('.caldera-forms-modal').removeClass('nav-up').addClass('nav-down');
    }
    lastScrollTop = st;
  });
})(jQuery);