hugo-theme-contentful/layouts/partials/head.html

<title>{{ if .IsHome }}{{ $.Site.Title | safeHTML }}{{ else }}{{ .Title | safeHTML }}{{ end }}</title>

{{- /* Only enable asset bundling in production */ -}}
{{- $style := resources.Get "css/main.css" -}}
{{- if hugo.IsProduction }}
  {{- $style = $style | resources.Minify | resources.Fingerprint -}}
{{- end }}
<link rel="stylesheet" href="{{ $style.Permalink }}" />

{{- /* Some sane <meta> tags default */ -}}
{{ hugo.Generator }}
<meta charset="utf-8">

{{- with .Site.Author }}
{{- $names := slice }}
{{- range . }}{{ $names = $names | append .name }}{{ end }}
<meta name="author" content="{{ delimit $names ", " (printf " %s " (i18n "and")) }}" />
{{- end }}

<meta name="viewport" content="width=device-width, initial-scale=1" />
<meta name="referrer" content="no-referrer" />
<meta name="description" content="{{ if (and (eq .Kind "home") .IsHome) }}{{ .Site.Title }}{{ else }}{{ .Summary | safeHTML }}{{ end }}" />
{{- template "_internal/twitter_cards.html" . }}
{{- template "_internal/opengraph.html" . }}


{{- /* Linking all of the output formats for discovery. */ -}}
{{- range .OutputFormats }}
{{- printf "<link rel=%q type=%q href=%q />" .Rel .MediaType.Type .Permalink | safeHTML }}
{{- end }}


{{- if hugo.IsProduction }}
    {{ template "_internal/google_analytics_async.html" . }}
    {{ template "_internal/disqus.html" . }}
{{- end }}


{{- /* Persistent theme.
It's a very small script so there's little effect on perceived performance. */ -}}
<script>
    const theme = window.localStorage.getItem('theme'); 
    if (theme) {
        document.documentElement.dataset.theme = theme;
    }
</script>