code: function(header) {
          header = $(header);
  
          var options = this.options,
              section = header.next(), // section
              index = header.data('accordion-index'),
              height = parseInt(section.data('accordion-height'), 10),
              isNode = (this.node && this.node.is(header));
  
          this.fireEvent('showing', [section, header, this.index]);
  
          // Allow simultaneous open and closed sections
          // Or allow the same section to collapse
          if (options.mode === 'click' && (options.multiple || options.collapsible && isNode)) {
              if (section.is(':shown') && this.node) {
                  section.css('max-height', 0).conceal(true);
                  header.aria('toggled', false).removeClass('is-active');
  
              } else {
                  section.css('max-height', height).reveal(true);
                  header.aria('toggled', true).addClass('is-active');
              }
  
          // Only one open at a time
          } else {
  
              // Exit early so we don't mess with animations
              if (isNode) {
                  return;
              }
  
              this.sections.css('max-height', 0).conceal(true);
              section.css('max-height', height).reveal(true);
  
              this.headers.aria('toggled', false).removeClass('is-active');
              header.aria('toggled', true).addClass('is-active');
          }
  
          this.index = index;
          this.node = header;
  
          this.fireEvent('shown', [section, header, index]);
      }
docs: Toggle the section display of a row via the header click/hover event.
  Take into account the multiple and collapsible options.
  
  @param {jQuery} header