docs: function($modal, callback) {
          var $input = $modal.querySelector('input');
          var $overlay = document.getElementById('overlay-'+$modal.id);
  
          // hide alerty with animation
          commonUse.removeClass($modal, 'alerty-show');
          commonUse.addClass($modal, 'alerty-hide');
  
          // remove alerty and other added elements
          setTimeout(function(){
            $overlay && commonUse.removeClass($overlay, 'active'), commonUse.removeClass(document.body, 'no-scrolling');
            
            commonUse.removeElement($modal);
            commonUse.removeElement($overlay);
            if (callback) {
              setTimeout(function(){
                !$input ? callback() : callback($input.value);  // handle prompt type, callback the input value
              }, 100);
            }
          },100);
        }