code: function closest (element, selector) {
      while (element && element.nodeType !== DOCUMENT_NODE_TYPE) {
          if (typeof element.matches === 'function' &&
              element.matches(selector)) {
            return element;
          }
          element = element.parentNode;
      }
  }
docs: Finds the closest parent that matches a selector.
  
  @param {Element} element
  @param {String} selector
  @return {Function}