Cacher is the code snippet organizer for pro developers

<?php
// Get Current Page Slug
$page_slug = ($post)? $post->post_name : '';

// Get Parent Page Slug
$parent_slug = ($post)? get_page_uri($post->post_parent) : '';

// Create Array of Global Navigation
$gnavArray = array(
	'advantage'  => '',
	'guide'     => '',
	'information'=> '',
	'price'      => '',
	'voice'      => '',
	'faq'        => '',
);

if(is_singular('voice') || is_archive('voice')) {

	// If Custom Post Type Pages
	$gnavArray['voice'] = (is_category())? '' : '_current';

} elseif(!empty($page_slug) ||!empty($parent_slug)) {

	// If Global Navigation Pages
	if(array_key_exists($page_slug,$gnavArray) || array_key_exists($parent_slug,$gnavArray)) {
		$arrayKey = (!empty($parent_slug))? $parent_slug : $page_slug;
		$gnavArray[$arrayKey] = '_current';
	}

}
?>

<header id="top" class="head _container">
	<nav class="head _inner">
		<ul class="head _gnav">
			<li class="head _gnav_item _logo "><a href="<?php echo home_url(); ?>/">外壁塗装一括見積.com</a></li>
			<li class="head _gnav_item _advantage <?php echo $gnavArray['advantage']; ?>">
				<a href="<?php echo get_bloginfo('url'); ?>/advantage/">当社の強み</a>
			</li>
			<li class="head _gnav_item _guide <?php echo $gnavArray['guide']; ?>">
				<a href="<?php echo get_bloginfo('url'); ?>/guide/">ご利用方法</a>
			</li>
			<li class="head _gnav_item _information <?php echo $gnavArray['information']; ?>">
				<a href="<?php echo get_bloginfo('url'); ?>/information/">お役立ち情報</a>
			</li>
			<li class="head _gnav_item">
				<img src="<?php echo get_blogInfo('template_directory'); ?>/img/common/price_inactive.png" alt="全国平均価格">
			</li>
			<?php /*
			<li class="head _gnav_item _price <?php echo $gnavArray['price']; ?>">
				<a href="<?php echo get_bloginfo('url'); ?>/price/">全国平均価格</a>
			</li>
			*/ ?>
			<li class="head _gnav_item _voice <?php echo $gnavArray['voice']; ?>">
				<a href="<?php echo get_bloginfo('url'); ?>/voice/">お客様の声</a>
			</li>
			<li class="head _gnav_item _faq <?php echo $gnavArray['faq']; ?>">
				<a href="<?php echo get_bloginfo('url'); ?>/faq/">よくある質問</a>
			</li>
		</ul>
	</nav>
</header>