hugo-PaperMod/layouts/partials/header.html

{{ if eq .Site.Params.defaultTheme "auto" }}
<script>
    if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
        document.body.classList.add('dark');
    }
</script>
{{ end }}
<header class="header">
    <nav class="nav">
        {{- if .IsHome }}
        <h1 class="logo"><a href="{{ "" | absLangURL }}">{{ .Site.Title }}</a></h1>
        {{- else }}
        <p class="logo"><a href="{{ "" | absLangURL }}">{{ .Site.Title }}</a></p>
        {{- end }}
        {{- if .Site.Menus.main }}
        <ul class="menu" id="menu" onscroll="menu_on_scroll()">
            {{- range .Site.Menus.main }}
            <li>
                <a href="{{ .URL | absLangURL}}">{{ .Name }}</a>
            </li>
            {{- end }}
        </ul>
        {{- end }}
    </nav>
</header>