Pure.io CSS Menu Walker

class Pure_Menu_Walker extends Walker {

	var $db_fields = array('parent' => 'menu_item_parent', 'id' => 'db_id');

	function start_lvl(&$output, $depth = 0, $args = array()) {
		$indent = str_repeat("", $depth);
		$output .= &quot;$indent<ul class=&#x27;pure-menu-children&#x27;>&quot;;
	}

	function end_lvl(&$output, $depth = 0, $args = array()) {
		$indent = str_repeat(&quot;&quot;, $depth);
		$output .= &quot;$indent</ul>&quot;;
	}

	function start_el(&$output, $item, $depth = 0, $args = array(), $id = 0) {

		global $wp_query;
		$indent = ($depth) ? str_repeat(&quot;&quot;, $depth) : &#x27;&#x27;;
		$class_names = $value = &#x27;&#x27;;
		$classes = empty($item->classes) ? array() : (array) $item->classes;

		/* Add active class */
		if (in_array(&#x27;current-menu-item&#x27;, $classes)) {
			$classes[] = &#x27;active&#x27;;
			unset($classes[&#x27;current-menu-item&#x27;]);
		}

		/* Check for children */
		$children = get_posts(array(&#x27;post_type&#x27; => &#x27;nav_menu_item&#x27;, &#x27;nopaging&#x27; => true, &#x27;numberposts&#x27; => 1, &#x27;meta_key&#x27; => &#x27;_menu_item_menu_item_parent&#x27;, &#x27;meta_value&#x27; => $item->ID));
		if (!empty($children)) {
			$classes[] = &#x27;has-sub pure-menu-has-children pure-menu-allow-hover&#x27;;
		}

		$class_names = join(&#x27; &#x27;, apply_filters(&#x27;nav_menu_css_class&#x27;, array_filter($classes), $item, $args));
		$class_names = $class_names ? &#x27; class=&quot;pure-menu-item &#x27; . esc_attr($class_names) . &#x27;&quot;&#x27; : &#x27;&#x27;;

		$id = apply_filters(&#x27;nav_menu_item_id&#x27;, &#x27;menu-item-&#x27;. $item->ID, $item, $args);
		$id = $id ? &#x27; id=&quot;&#x27; . esc_attr($id) . &#x27;&quot;&#x27; : &#x27;&#x27;;

		$output .= $indent . &#x27;<li&#x27; . $id . $value . $class_names .&#x27;>&#x27;;

		$attributes  = ! empty($item->attr_title) ? &#x27; title=&quot;&#x27;  . esc_attr($item->attr_title) .&#x27;&quot;&#x27; : &#x27;&#x27;;
		$attributes .= ! empty($item->target)     ? &#x27; target=&quot;&#x27; . esc_attr($item->target    ) .&#x27;&quot;&#x27; : &#x27;&#x27;;
		$attributes .= ! empty($item->xfn)        ? &#x27; rel=&quot;&#x27;    . esc_attr($item->xfn       ) .&#x27;&quot;&#x27; : &#x27;&#x27;;
		$attributes .= ! empty($item->url)        ? &#x27; href=&quot;&#x27;   . esc_attr($item->url       ) .&#x27;&quot;&#x27; : &#x27;&#x27;;

		$item_output = $args->before;
		$item_output .= &#x27;<a&#x27;. $attributes .&#x27; class=&quot;pure-menu-link&quot;>&#x27;;
		$item_output .= $args->link_before . apply_filters(&#x27;the_title&#x27;, $item->title, $item->ID) . $args->link_after;
		$item_output .= &#x27;</a>&#x27;;
		$item_output .= $args->after;

		$output .= apply_filters(&#x27;walker_nav_menu_start_el&#x27;, $item_output, $item, $depth, $args);
	}

	function end_el(&$output, $item, $depth = 0, $args = array()) {
		$output .= &quot;</li>&quot;;
	}
}