function _setHelperLayerPosition(helperLayer) {
    if (helperLayer) {
      //prevent error when `this._currentStep` in undefined
      if (!this._introItems[this._currentStep]) return;

      var currentElement  = this._introItems[this._currentStep],
          elementPosition = _getOffset(currentElement.element),
          widthHeightPadding = 10;

      // If the target element is fixed, the tooltip should be fixed as well.
      // Otherwise, remove a fixed class that may be left over from the previous
      // step.
      if (_isFixed(currentElement.element)) {
        helperLayer.className += ' introjs-fixedTooltip';
      } else {
        helperLayer.className = helperLayer.className.replace(' introjs-fixedTooltip', '');
      }

      if (currentElement.position == 'floating') {
        widthHeightPadding = 0;
      }

      //set new position to helper layer
      helperLayer.setAttribute('style', 'width: ' + (elementPosition.width  + widthHeightPadding)  + 'px; ' +
                                        'height:' + (elementPosition.height + widthHeightPadding)  + 'px; ' +
                                        'top:'    + (elementPosition.top    - 5)   + 'px;' +
                                        'left: '  + (elementPosition.left   - 5)   + 'px;');

    }
  }
Update the position of the helper layer on the screen

@api private
@method _setHelperLayerPosition
@param {Object} helperLayer