govuk-frontend/dist/govuk/components/accordion/template-default.html

GOV.UK Frontend contains the code you need to start building a user interface for government platforms and services.

<div class="govuk-accordion" data-module="govuk-accordion" id="default-example">
  <div class="govuk-accordion__section">
    <div class="govuk-accordion__section-header">
      <h2 class="govuk-accordion__section-heading">
        <span class="govuk-accordion__section-button" id="default-example-heading-1">
          Section A
        </span>
      </h2>
    </div>
    <div id="default-example-content-1" class="govuk-accordion__section-content">
      <p class="govuk-body">
        We need to know your nationality so we can work out which elections you’re entitled to vote in. If you cannot provide your nationality, you’ll have to send copies of identity documents through the post.
      </p>
    </div>
  </div>
  <div class="govuk-accordion__section">
    <div class="govuk-accordion__section-header">
      <h2 class="govuk-accordion__section-heading">
        <span class="govuk-accordion__section-button" id="default-example-heading-2">
          Section B
        </span>
      </h2>
    </div>
    <div id="default-example-content-2" class="govuk-accordion__section-content">
      <ul class="govuk-list govuk-list--bullet">
        <li>Example item 2</li>
      </ul>
    </div>
  </div>
</div>