text: window.addEventListener('load', event => {
      parallax(event);
  });
  window.addEventListener('resize', event => {
      parallax(event);
  });
  window.addEventListener('scroll', event => {
      parallax(event);
  });
  
  function parallax(event) {
      event.preventDefault();
      if (document.body.clientWidth >= 1087) {
          var col1Name = document.getElementById('left_column');
          var col2Name = document.getElementById('center_column');
          var col3Name = document.getElementById('right_column');
          var col1 = col1Name.offsetHeight;
          var col2 = col2Name.offsetHeight;
          var col3 = col3Name.offsetHeight;
          var cols = document.getElementById('parallax');
          var topOfColumns = cols.offsetTop;
          var max = Math.max(col1, col2, col3);
          var scrolltop = window.scrollY;
          var distance = scrolltop - topOfColumns;
          if (distance > 0) {
              col1Name.style.marginTop = getTop(col1, max) + 'px';
              col2Name.style.marginTop = getTop(col2, max) + 'px';
              col3Name.style.marginTop = getTop(col3, max) + 'px';
          } else {
              col1Name.style.marginTop = '0';
              col2Name.style.marginTop = '0';
              col3Name.style.marginTop = '0';
          }
      }
  }
  
  function getTop(col, max) {
      var height = window.innerHeight;
      var cols = document.getElementById('parallax');
      var topOfColumns = cols.offsetTop;
      var columns = cols.offsetHeight - height;
      var travel = max - col;
      var scrollInterval = columns / travel;
  
      var scrolltop = window.scrollY;
      var distance = scrolltop - topOfColumns;
  
  
      if (scrolltop < topOfColumns + max - height + 20) {
          return Math.floor(distance / scrollInterval);
      } else {
          return travel;
      }
  }
  