markusgraf_ch/layouts/partials/header.html

<header>
  <nav class="navbar navbar-expand-lg navbar-light bg-light">
    <div class="container">
      <h1><a class="navbar-brand" href="{{ "/" | relLangURL }}">{{ .Site.Title }}</a></h1>
      <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
        <span class="navbar-toggler-icon"></span>
      </button>
      {{ partial "nav.html" . }}
    </div>
  </nav>
</header>