text: jQuery(document).ready(function($){
      var timelineBlocks = $('.cd-timeline-block'),
          offset = 0.8;
  
      //hide timeline blocks which are outside the viewport
      hideBlocks(timelineBlocks, offset);
  
      //on scolling, show/animate timeline blocks when enter the viewport
      $(window).on('scroll', function(){
          (!window.requestAnimationFrame)
              ? setTimeout(function(){ showBlocks(timelineBlocks, offset); }, 100)
              : window.requestAnimationFrame(function(){ showBlocks(timelineBlocks, offset); });
      });
  
      function hideBlocks(blocks, offset) {
          blocks.each(function(){
              ( $(this).offset().top > $(window).scrollTop()+$(window).height()*offset ) && $(this).find('.cd-timeline-img, .cd-timeline-content').addClass('is-hidden');
          });
      }
  
      function showBlocks(blocks, offset) {
          blocks.each(function(){
              ( $(this).offset().top <= $(window).scrollTop()+$(window).height()*offset && $(this).find('.cd-timeline-img').hasClass('is-hidden') ) && $(this).find('.cd-timeline-img, .cd-timeline-content').removeClass('is-hidden').addClass('bounce-in');
          });
      }
  });