Code javascript thêm nút tới lùi các section trên trang flatsome

Code javascript thêm nút tới lùi các section trên trang flatsome

Thêm HTML và CSS

<ul class="nav-section">
    <li>
        <span id="prev-section"> <i class="fas fa-angle-up"></i></span>
    </li>
    <li>
        <span id="next-section"> <i class="fas fa-angle-down"></i></span>
    </li>
</ul>

<style>
.nav-section{
    position: fixed;
    right: 0;
    bottom: 20%;
    list-style: none;
    margin: 0;
    padding: 0;
    z-index: 99999;
}

.nav-section span{
  display: block;
  width: 40px;
  height: 40px;
  color: #FFF;
  background: #1a7a68;
  line-height: 35px;
  text-align: center;
}

.nav-section span:hover{
    cursor: pointer;
}

</style>

Thêm Javascript

function scroll_to_element(elementtoScrollToID) {
  jQuery([document.documentElement, document.body]).animate({
    scrollTop: jQuery(elementtoScrollToID).offset().top - 120
  }, 500);
}

function find_current_section() {
  var currentScreenPosition = jQuery(document).scrollTop();

if (currentScreenPosition <= 100) { jQuery('#content > .section').first().addClass('current');
    return false;
  }

  jQuery('#content > .section').each(function (section) {
    if (currentScreenPosition > jQuery(this).position().top && currentScreenPosition < jQuery(this).position().top + jQuery(this).height()) {
      jQuery(this).addClass('current');
      return false;
    }
  });
}

jQuery(function () {
  find_current_section();

  var all_sections = jQuery('#content > .section');
  jQuery(window).scroll(function () {
    var currentScreenPosition = jQuery(document).scrollTop();
    jQuery(all_sections).each(function (section) {

      if (currentScreenPosition > jQuery(this).position().top && currentScreenPosition < jQuery(this).position().top + jQuery(this).height()) {
        jQuery(this).addClass('current');
      } else {
        jQuery(this).removeClass('current');
      }
    });

    if (currentScreenPosition >= jQuery('#content > .section').last().position().top ){
      jQuery('#content > .section').removeClass('current');
      jQuery('#content > .section').last().addClass('current');

    }

  });

  jQuery('#prev-section').on('click', function (e) {
    e.preventDefault();
    var element = jQuery('#content > .section.current').prev();
    if (element) {
      scroll_to_element(element)
    }
  });

  jQuery('#next-section').on('click', function (e) {
    e.preventDefault();
    var element = jQuery('#content > .section.current').next();
    if (element) {
      scroll_to_element(element)
    }
  })

});