<!– Google Tag Manager –>

{% if site.google-tag_key == "Google Tag Manager key goes here" or site.google-tag_key == nil or site.google-tag_key == '' %}<!-- =========================================================================================
  YOU NEED TO PUT THE GOOGLE TAG KEY IN THE _config.yml FILE!
  ============================================================================================ -->{% endif %}
{% if jekyll.environment == "publish" %}{% if site.google-tag_key != "Google Tag Manager key goes here" and site.google-tag_key != nil %}
<script>
  (function(w, d, s, l, i) {
    w[l] = w[l] || [];
    w[l].push({
      'gtm.start': new Date().getTime(),
      event: 'gtm.js'
    });
    var f = d.getElementsByTagName(s)[0],
      j = d.createElement(s),
      dl = l != 'dataLayer' ? '&l=' + l : '';
    j.async = true;
    j.src =
      'https://www.googletagmanager.com/gtm.js?id=' + i + dl;
    f.parentNode.insertBefore(j, f);
  })(window, document, 'script', 'dataLayer', '{{ site.google-tag_key }}');
</script>
{% endif %}{%- endif -%}
<!-- End Google Tag Manager -->