hugo-theme-wondermod/layouts/partials/header.html

{{- /* theme-toggle is enabled */}}
{{- if (not .Site.Params.disableThemeToggle) }}
{{- /* theme is light */}}
{{- if (eq .Site.Params.defaultTheme "light") }}
<script>
    if (localStorage.getItem("pref-theme") === "dark") {
        document.body.classList.add('dark');
    }

</script>
{{- /* theme is dark */}}
{{- else if (eq .Site.Params.defaultTheme "dark") }}
<script>
    if (localStorage.getItem("pref-theme") === "light") {
        document.body.classList.remove('dark')
    }

</script>
{{- else }}
{{- /* theme is auto */}}
<script>
    if (localStorage.getItem("pref-theme") === "dark") {
        document.body.classList.add('dark');
    } else if (localStorage.getItem("pref-theme") === "light") {
        document.body.classList.remove('dark')
    } else if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
        document.body.classList.add('dark');
    }

</script>
{{- end }}
{{- /* theme-toggle is disabled and theme is auto */}}
{{- else if (and (ne .Site.Params.defaultTheme "light") (ne .Site.Params.defaultTheme "dark"))}}
<script>
    if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
        document.body.classList.add('dark');
    }

</script>
{{- end }}

<header class="header">
    <nav class="nav">
        <div class="logo">
            {{- $label_text := (.Site.Params.label.text | default .Site.Title) }}
            {{- if .Site.Title }}
            <a href="{{ "" | absLangURL }}" accesskey="h" title="{{ $label_text }} (Alt + H)">
                {{- if .Site.Params.label.icon }}
                <img src="{{- .Site.Params.label.icon | absURL -}}" alt="logo" aria-label="logo"
                    height="{{- .Site.Params.label.iconHeight | default " 30px" -}}">
                {{- end -}}
                {{- $label_text -}}
            </a>
            {{- end }}
            <span class="logo-switches">
                {{- if (not .Site.Params.disableThemeToggle) }}
                <button id="theme-toggle" accesskey="t" title="(Alt + T)">
                    <svg id="moon" xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"
                        fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"
                        stroke-linejoin="round">
                        <path d="M21 12.79A9 9 0 1 1 11.21 3 7 7 0 0 0 21 12.79z"></path>
                    </svg>
                    <svg id="sun" xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24"
                        fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round"
                        stroke-linejoin="round">
                        <circle cx="12" cy="12" r="5"></circle>
                        <line x1="12" y1="1" x2="12" y2="3"></line>
                        <line x1="12" y1="21" x2="12" y2="23"></line>
                        <line x1="4.22" y1="4.22" x2="5.64" y2="5.64"></line>
                        <line x1="18.36" y1="18.36" x2="19.78" y2="19.78"></line>
                        <line x1="1" y1="12" x2="3" y2="12"></line>
                        <line x1="21" y1="12" x2="23" y2="12"></line>
                        <line x1="4.22" y1="19.78" x2="5.64" y2="18.36"></line>
                        <line x1="18.36" y1="5.64" x2="19.78" y2="4.22"></line>
                    </svg>
                </button>
                {{- end }}

                {{- $lang := .Lang}}
                {{- $separator := or $label_text (not .Site.Params.disableThemeToggle)}}
                {{- with $.Site.Home.AllTranslations }}
                <ul class="lang-switch">
                    {{- if $separator }}<li>|</li>{{ end }}
                    {{- range . -}}
                    {{- if ne $lang .Lang }}
                    <li>
                        <a href="{{- .Permalink -}}" title="{{ .Language.Params.languageAltTitle | default (.Language.LanguageName | emojify) | default (.Lang | title) }}"
                            aria-label="{{ .Language.LanguageName | default (.Lang | title) }}">
                            {{- if (and $.Site.Params.displayFullLangName (.Language.LanguageName)) }}
                            {{- .Language.LanguageName | emojify -}}
                            {{- else }}
                            {{- .Lang | title -}}
                            {{- end -}}
                        </a>
                    </li>
                    {{- end -}}
                    {{- end}}
                </ul>
                {{- end }}
            </span>
        </div>
        {{- $currentPage := . }}
        <ul id="menu">
            {{- range .Site.Menus.main }}
            {{- $menu_item_url := (cond (strings.HasSuffix .URL "/") .URL (printf "%s/" .URL) ) | absLangURL }}
            {{- $page_url:= $currentPage.Permalink | absLangURL }}
            {{- $is_search := eq ($.Site.GetPage .KeyName).Layout `search` }}
            <li>
                <a href="{{ .URL | absLangURL }}" title="{{ .Title | default .Name }} {{- cond $is_search (" (Alt + /)" | safeHTMLAttr) ("" | safeHTMLAttr ) }}"
                {{- cond $is_search (" accesskey=/" | safeHTMLAttr) ("" | safeHTMLAttr ) }}>
                    <span {{- if eq $menu_item_url $page_url }} class="active" {{- end }}>
                        {{- .Pre }}
                        {{- .Name -}}
                        {{ .Post -}}
                    </span>
                </a>
            </li>
            {{- end }}
        </ul>
    </nav>
</header>