website/layouts/errorpages/single.html

{{ define "stylesheet" }}{{ $sass := resources.Get "/errorpages.scss" }}{{ $style := $sass | resources.ToCSS }}
    <link rel="stylesheet" href="{{ $style.Permalink }}" type="text/css" media="screen" rel="preload" />
{{ end }}

{{ define "main" }}
<main>
  <div class="container">
    <section>
      <header>
        <h2>{{ .Params.heading }}</h2>
        <span class="subtitle">{{.Params.subheading}}</span>
      </header>
      {{.Content}}
    </section>
  </div>
</main>
{{ end }}