<script type="application/ld+json">
    {
      "@context": "https://schema.org",
      "@type": "BreadcrumbList",
      "itemListElement": [{
        "@type": "ListItem",
        "position": 1,
        "name": "第一層商品種類",
        "item": "第一層商品網址"
      },
   
      ,{
        "@type": "ListItem",
        "position": 2,
        "name": "第二層商品種類",
        "item": "第二層商品網址"
      }
     
   
      ,{
        "@type": "ListItem",
        "position": 3,
        "name": "第三層商品種類",
        "item": "第三層商品網址"
      }
     
      ]
    }
</script>