{%- if jekyll.environment == 'production' and site.google_tag_manager.tracking_id -%}
  <!-- Google Tag Manager (noscript) -->
  <noscript><iframe src="https://www.googletagmanager.com/ns.html?id={{ site.google_tag_manager.tracking_id }}"
    height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
    <!-- End Google Tag Manager (noscript) -->
{%- endif -%}