hugo-theme-relearn/layouts/_default/_markup/render-blockquote.html

{{- $alerttype := .AlertType }}
{{- $text := .Text }}
{{- if not site.Params.disableBlockquoteNoticeSupport }}
  {{- range findRESubmatch "^(<p>)?\\[!(\\w+)\\]\\n(.*?)(</p>)?\\s*$" $text 1 }}
    {{- $alerttype = lower (index . 2) }}
    {{- $text = printf "%s%s%s" (index . 1) (index . 3) (index . 4) }}
  {{- end }}
{{- end }}
{{- if $alerttype }}
  {{- partial "shortcodes/notice.html" (dict
    "page" .Page
    "style" $alerttype
    "content" $text
  ) }}
{{- else }}
<blockquote>
  {{- $text | safeHTML }}
</blockquote>
{{- end }}