// --- 6. 【階層可視化版】少しずつずらして構造をわかりやすく ---

function get_my_ultimate_breadcrumb_html() {
    if (!is_single() || get_post_type() !== 'post') return '';
    global $post;

    $list_html = '<div class="my-custom-breadcrumb">';
    $list_html .= '<div class="bc-header"><span>GUIDE</span> 本記事の位置づけ</div><ul>';
    $list_html .= '<li class="bc-level-0"><a href="'.home_url('/').'">ホーム</a></li>';

    $level = 1;

    // カテゴリー階層
    $cats = wp_get_post_categories($post->ID);
    if (!empty($cats)) {
        $cat_id = $cats[0];
        $cat_ancestors = array_reverse(get_ancestors($cat_id, 'category'));
        foreach ($cat_ancestors as $caid) {
            $ca = get_category($caid);
            $list_html .= '<li class="bc-level-'.$level.'"><a href="'.get_category_link($caid).'">'.esc_html($ca->name).'<b class="bc-tag">親カテゴリー</b></a></li>';
            $level++;
        }
        $c = get_category($cat_id);
        $list_html .= '<li class="bc-level-'.$level.'"><a href="'.get_category_link($cat_id).'"><span>'.esc_html($c->name).'</span><b class="bc-tag">カテゴリー</b></a></li>';
        $level++;
    }

    // 記事の親子階層
    $ancestors = array_reverse(get_post_ancestors($post->ID));
    foreach ($ancestors as $aid) {
        $list_html .= '<li class="bc-level-'.$level.'"><a href="'.get_permalink($aid).'">'.get_the_title($aid).'<b class="bc-tag">親記事</b></a></li>';
        $level++;
    }
    
    // 現在のページ
    $list_html .= '<li class="bc-level-'.$level.' current-item"><span>'.get_the_title().'</span> <span class="now-here">現在のページ</span></li>';
    $list_html .= '</ul></div>';

    $style = '
    <style>
    .my-custom-breadcrumb { 
        display: block !important; 
        margin: 20px 0 40px 0 !important; 
        padding: 28px 30px 28px 45px !important; /* 左側に線のスペースを確保 */
        font-size: 14px !important; 
        line-height: 1.6 !important; 
        background: #ffffff !important; 
        border: 2px solid #e1f5fe !important; 
        border-radius: 18px !important; 
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05) !important; 
        box-sizing: border-box !important;
        width: 100% !important;
        opacity: 0;
        transition: opacity 0.6s ease;
    }
    .bc-header { 
        display: flex; align-items: center; gap: 10px;
        font-weight: bold; font-size: 13px; color: #455a64; 
        margin-bottom: 20px !important;
        margin-left: -15px !important; /* ヘッダーは少し戻す */
    }
    .bc-header span {
        background: #0288d1; color: #ffffff; 
        padding: 2px 9px; border-radius: 4px; font-size: 10px;
    }
    .my-custom-breadcrumb ul { list-style: none !important; margin: 0 !important; padding: 0 !important; }
    .my-custom-breadcrumb li { 
        display: flex !important; align-items: center !important; 
        padding: 10px 0 !important; position: relative !important;
        color: #333333 !important;
    }

    /* 階層をずらす（インデント設定） */
    .bc-level-1 { margin-left: 20px !important; }
    .bc-level-2 { margin-left: 40px !important; }
    .bc-level-3 { margin-left: 60px !important; }
    .bc-level-4 { margin-left: 80px !important; }
    .bc-level-5 { margin-left: 100px !important; }

    /* L字コネクタ線：すべての階層（ホーム以外）に適用 */
    .my-custom-breadcrumb li:not(.bc-level-0)::before { 
        content: "" !important; 
        position: absolute !important; 
        left: -18px; /* 線の横位置 */
        top: -12px; /* 上の項目からの距離 */
        bottom: 50%;
        border-left: 1.5px solid #b0bec5;
        border-bottom: 1.5px solid #b0bec5;
        width: 12px;
    }

    /* タグのデザイン：水色背景に濃い文字 */
    .bc-tag { 
        font-size: 10px; color: #01579b !important; 
        background: #e3f2fd !important;
        padding: 1px 8px; border-radius: 4px; margin-left: 12px; font-weight: bold;
        white-space: nowrap; border: 1px solid #bbdefb;
    }
    
    .my-custom-breadcrumb li a { 
        text-decoration: none !important; 
        color: #0277bd !important; 
        font-weight: 600; 
    }
    .my-custom-breadcrumb li a:hover { color: #01579b !important; text-decoration: underline !important; }
    
    .current-item { font-weight: 700; color: #212121 !important; }
    
    /* 現在のページ：濃い水色に白文字 */
    .now-here { 
        display: inline-block; margin-left: 12px; 
        color: #ffffff !important; 
        background: #03a9f4 !important; 
        padding: 2px 10px; border-radius: 4px; font-size: 11px; font-weight: bold;
    }
    
    @media screen and (max-width: 767px) { 
        .my-custom-breadcrumb { padding: 22px 15px 22px 25px !important; }
        /* スマホではズレ幅を小さくして画面外に出るのを防ぐ */
        .bc-level-1 { margin-left: 10px !important; }
        .bc-level-2 { margin-left: 20px !important; }
        .bc-level-3 { margin-left: 30px !important; }
        .bc-level-4 { margin-left: 40px !important; }
        .bc-level-5 { margin-left: 50px !important; }
    }
    </style>';

    $script = "
    <script>
    (function() {
        function moveBreadcrumb() {
            var bc = document.querySelector('.my-custom-breadcrumb');
            var title = document.querySelector('h1.entry-title') || document.querySelector('h1.post-title') || document.querySelector('h1');
            if (bc && title) {
                title.parentNode.insertBefore(bc, title.nextSibling);
                bc.style.opacity = '1';
            }
        }
        window.addEventListener('load', moveBreadcrumb);
    })();
    </script>";

    return $style . $list_html . $script;
}

add_action('wp_footer', function() {
    echo get_my_ultimate_breadcrumb_html();
});
<title>XML Sitemap</title><style type="text/css">
					body {
						font-family:"Lucida Grande","Lucida Sans Unicode",Tahoma,Verdana;
						font-size:13px;
					}
					
					#intro {
						background-color:#cfebf7;
						border:1px #2580B2 solid;
						padding:5px 13px 5px 13px;
						margin:10px;
					}
					
					#intro p {
						line-height:16.8667px;
					}
					#intro strong {
						font-weight:normal;
					}
					
					td {
						font-size:11px;
					}
					
					th {
						text-align:left;
						padding-right:30px;
						font-size:11px;
					}
					
					tr.high {
						background-color:whitesmoke;
					}
					
					#footer {
						padding:2px;
						margin-top:10px;
						font-size:8pt;
						color:gray;
					}
					
					#footer a {
						color:gray;
					}
					
					a {
						color:black;
					}
				</style><h1>XML Sitemap Index</h1><div id="intro"><p>
                This XML sitemap is used by search engines which follow the <a rel="external nofollow" href="https://sitemaps.org">XML sitemap standard</a>. This file contains links to sub-sitemaps, follow them to see the actual sitemap content.
            </p><p>
                This file was dynamically generated using the <a rel="external nofollow" href="https://wordpress.org/">WordPress</a> content management system and <strong><a rel="external nofollow" href="https://auctollo.com/products/google-xml-sitemap-generator/" title="XML Sitemap Generator for Google">XML Sitemap Generator for Google</a></strong> by <a rel="external nofollow" href="https://auctollo.com/">Auctollo</a>.
            </p></div><div id="content"><table><tr style="border-bottom:1px black solid"><th>URL of sub-sitemap</th><th>Last modified (GMT)</th></tr><tr><td><a href="https://law-text.com/sitemap-misc.html">https://law-text.com/sitemap-misc.html</a></td><td>2026-04-21T21:04:12+00:00</td></tr><tr class="high"><td><a href="https://law-text.com/category-sitemap.html">https://law-text.com/category-sitemap.html</a></td><td>2026-04-21T21:04:12+00:00</td></tr><tr><td><a href="https://law-text.com/post-sitemap.html">https://law-text.com/post-sitemap.html</a></td><td>2026-04-21T21:04:12+00:00</td></tr><tr class="high"><td><a href="https://law-text.com/page-sitemap.html">https://law-text.com/page-sitemap.html</a></td><td>2026-04-15T22:41:24+00:00</td></tr></table></div><div id="footer"><p>
						Dynamically generated with <a rel="external nofollow" href="https://auctollo.com/products/google-xml-sitemap-generator/" title="XML Sitemap Generator for Google">XML Sitemap Generator for Google</a> by <a rel="external nofollow" href="https://auctollo.com/">Auctollo</a>. This XSLT template is released under the GPL and free to use.
            		</p><p>
	                    If you have problems with your sitemap please visit the <a rel="external nofollow" href="https://auctollo.com/products/google-xml-sitemap-generator/help/" title="Frequently Asked Questions">FAQ</a> or the <a rel="external nofollow" href="https://wordpress.org/support/plugin/google-sitemap-generator">support forum</a>.
            		</p></div>