<div class="govuk-panel govuk-panel--confirmation">
  <h1 class="govuk-panel__title">
    Application complete
  </h1>
  
  <div class="govuk-panel__body">
    Your reference number<br><strong>HDJ2123F</strong>
  </div>
  
</div>

{{ govukPanel({
  "titleText": "Application complete",
  "html": "Your reference number<br><strong>HDJ2123F</strong>"
}) }}