echo/website/layouts/partials/sidenav.html

<nav id="sidenav" class="w3-sidenav w3-collapse">
  <span class="w3-closenav w3-xxlarge w3-hide-large" onclick="closeSidenav()">
    &times;
  </span>
  <a class="w3-btn w3-white w3-border w3-border-theme w3-round-xlarge support-us" href="/support-echo">
    <i class="fa fa-heart" aria-hidden="true"></i> Support Echo
  </a>
  {{ $currentNode := . }}
  <div class="w3-hide-large menu">
    {{ range .Site.Menus.main }}
      <a{{ if or ($currentNode.HasMenuCurrent "main" .) ($currentNode.IsMenuCurrent "main" .) }} class="active"{{ end }} href="{{ .URL }}">
        <div class="w3-xlarge w3-padding-top">{{ .Name }}</div>
      </a>
    {{ end }}
  </div>
  <div class="sub-menu">
    {{ if .IsPage }}
      {{ range where .Site.Menus.main "Identifier" .Type }}
        <div class="w3-xlarge w3-padding-top">{{ .Pre }} {{ .Name }}</div>
        {{ range .Children }}
          <a{{ if $currentNode.IsMenuCurrent "main" . }} class="active"{{ end }} href="{{ .URL }}">
            {{ .Name }}
          </a>
        {{ end }}
      {{ end }}
  {{ end }}
  </div>
</nav>