gohugo-theme-ananke/layouts/404.html

{{ define "header" }}{{ partial "page-header.html" . }}{{ end }}
{{ define "main" }}
{{ $currentPageUrl := .URL }}
{{ $currentSection := where .Site.Pages "Section" .Section }}
    <article class="center cf pv5 measure-wide-l">
      <h1>
        This is not the page you were looking for
      </h1>
    </article>
{{ end }}