function addElClass(element, classToAdd) {
  if (!hasElClass(element, classToAdd)) {
    element.className = element.className === '' ? classToAdd : element.className + ' ' + classToAdd;
  }
}
/**
 * Add a CSS class name to an element
 *
 * @param {Element} element    Element to add class name to
 * @param {String} classToAdd Classname to add
 * @function addElClass
 */
Add a CSS class name to an element
@param {Element} element    Element to add class name to
@param {String} classToAdd Classname to add
@function addElClass
Add a CSS class name to an element @param { Element } element Element to add class name to @param { String } classToAdd Classname to add @function addElClass
function addElClass(element, classToAdd) {
  if (!hasElClass(element, classToAdd)) {
    element.className = element.className === '' ? classToAdd : element.className + ' ' + classToAdd;
  }
}
function addElClass ( element , classToAdd ) { if ( ! hasElClass ( element , classToAdd ) ) { element . className = element . className === '' ? classToAdd : element . className + ' ' + classToAdd ; } }
Add a CSS class name to an element
 @param {Element} element    Element to add class name to
 @param {String} classToAdd Classname to add
 @function addElClass
Add a CSS class name to an element @param { Element } element Element to add class name to @param { String } classToAdd Classname to add @function addElClass