sakrecoer-mother-web/_includes/navmenu.html

<div id="navigation">
  {% if page.collection == 'tracks' %}
  <a href="{{ site.baseurl }}./#{{ page.uid }}" alt="Back" title="Back">
  {% elsif page.url != '/music/' %}
  <a href="{{ site.baseurl }}/music/" alt="Music" title="Music">
  {% else %}
  <a href="{{ site.baseurl }}/" alt="Back" title="About">
  {% endif %}
    <img src="{{ site.baseurl }}/assets/img/sakrecoer-logo.svg" width="125px" height="125px" alt="Sakrecoer Logo" />
  </a>
</div>
{% if page.collection != 'tracks' %}
<script type="text/javascript">
  $(window).scroll(function(){
      $("#navigation").css("opacity", 0 + $(window).scrollTop() / 250);
  });
</script>
{% else %}
<script type="text/javascript">
  $(window).scroll(function(){
      $("#navigation").css("opacity", 1 - $(window).scrollTop() / 250);
  });
</script>
{% endif %}