document.addEventListener("DOMContentLoaded", function(event) {
  var activities = document.getElementById("dvContainer");
  activities.addEventListener("change", function() {
      if(activities.childElementCount > 0)
      {
          activities.classList.add("displayZero");
      }
      else {
        activities.classList.remove("displayZero");
      }
      //console.log('ajay');
});
});