Vertical Scroll Bar Counter

  // HTML
      <!-- VERTICAL SCROLL BAR -->
    <div class="verticalScrollBar">
      <div class="verticalScrollSlider"></div>
    </div>
  // HTML
  
  // CSS
  // VERTICAL SCROLL BAR
.verticalScrollBar {
  position: fixed;
  width: 100%;
  z-index: 10000;

  .verticalScrollSlider {
    display: block;
    position: absolute;
    height: 3px;
    width: 100%;
    background-color: #000;
    z-index: 1000;
  }
}

  // CSS
  
  
  // jQuery
  
  // VERTICAL SCROLL COUNTER
  $(window).scroll(function () {
    let wintop = $(window).scrollTop(),
      docheight = $(document).height(),
      winheight = $(window).height()

    let scrolled = ((wintop / (docheight - winheight)) * 100).toFixed()
    // console.log(scrolled)

    $(".verticalScrollSlider").css({ width: scrolled + "%" })
  })