text: /**
   * File navigation.js.
   *
   * Handles toggling the navigation menu for small screens and enables TAB key
   * navigation support for dropdown menus.
   */
  ( function() {
    var container, button, menu, links, i, len;
  
    container = document.getElementById( 'site-navigation' );
    if ( ! container ) {
      return;
    }
  
    button = container.getElementsByTagName( 'button' )[0];
    if ( 'undefined' === typeof button ) {
      return;
    }
  
    menu = container.getElementsByTagName( 'ul' )[0];
  
    // Hide menu toggle button if menu is empty and return early.
    if ( 'undefined' === typeof menu ) {
      button.style.display = 'none';
      return;
    }
  
    menu.setAttribute( 'aria-expanded', 'false' );
    if ( -1 === menu.className.indexOf( 'nav-menu' ) ) {
      menu.className += ' nav-menu';
    }
  
    button.onclick = function() {
      if ( -1 !== container.className.indexOf( 'toggled' ) ) {
        container.className = container.className.replace( ' toggled', '' );
        button.setAttribute( 'aria-expanded', 'false' );
        menu.setAttribute( 'aria-expanded', 'false' );
      } else {
        container.className += ' toggled';
        button.setAttribute( 'aria-expanded', 'true' );
        menu.setAttribute( 'aria-expanded', 'true' );
      }
    };
  
    // Get all the link elements within the menu.
    links    = menu.getElementsByTagName( 'a' );
  
    // Each time a menu link is focused or blurred, toggle focus.
    for ( i = 0, len = links.length; i < len; i++ ) {
      links[i].addEventListener( 'focus', toggleFocus, true );
      links[i].addEventListener( 'blur', toggleFocus, true );
    }
  
    /**
     * Sets or removes .focus class on an element.
     */
    function toggleFocus() {
      var self = this;
  
      // Move up through the ancestors of the current link until we hit .nav-menu.
      while ( -1 === self.className.indexOf( 'nav-menu' ) ) {
  
        // On li elements toggle the class .focus.
        if ( 'li' === self.tagName.toLowerCase() ) {
          if ( -1 !== self.className.indexOf( 'focus' ) ) {
            self.className = self.className.replace( ' focus', '' );
          } else {
            self.className += ' focus';
          }
        }
  
        self = self.parentElement;
      }
    }
  
    /**
     * Toggles `focus` class to allow submenu access on tablets.
     */
    ( function( container ) {
      var touchStartFn, i,
        parentLink = container.querySelectorAll( '.menu-item-has-children > a, .page_item_has_children > a' );
  
      if ( 'ontouchstart' in window ) {
        touchStartFn = function( e ) {
          var menuItem = this.parentNode, i;
  
          if ( ! menuItem.classList.contains( 'focus' ) ) {
            e.preventDefault();
            for ( i = 0; i < menuItem.parentNode.children.length; ++i ) {
              if ( menuItem === menuItem.parentNode.children[i] ) {
                continue;
              }
              menuItem.parentNode.children[i].classList.remove( 'focus' );
            }
            menuItem.classList.add( 'focus' );
          } else {
            menuItem.classList.remove( 'focus' );
          }
        };
  
        for ( i = 0; i < parentLink.length; ++i ) {
          parentLink[i].addEventListener( 'touchstart', touchStartFn, false );
        }
      }
    }( container ) );
  } )();
  