jQueryCSS($obj, propertyNames) {
    const result = {};
    $.each(propertyNames, (idx, propertyName) => {
      result[propertyName] = $obj.css(propertyName);
    });
    return result;
  }
@method jQueryCSS

[workaround] for old jQuery
passing an array of style properties to .css()
will result in an object of property-value pairs.
(compability with version < 1.9)

@private
@param  {jQuery} $obj
@param  {Array} propertyNames - An array of one or more CSS properties.
@return {Object}