jekyll-theme-chirpy/_includes/post-nav.html

<!-- Navigation buttons at the bottom of the post. -->

<div class="post-navigation d-flex justify-content-between">
  {% if page.previous.url %}
    <a
      href="{{ site.baseurl }}{{ page.previous.url }}"
      class="btn btn-outline-primary"
      prompt="{{ site.data.locales[include.lang].post.button.previous }}"
    >
      <p>{{ page.previous.title }}</p>
    </a>
  {% else %}
    <div
      class="btn btn-outline-primary disabled"
      prompt="{{ site.data.locales[include.lang].post.button.previous }}"
    >
      <p>-</p>
    </div>
  {% endif %}

  {% if page.next.url %}
    <a
      href="{{ site.baseurl }}{{page.next.url}}"
      class="btn btn-outline-primary"
      prompt="{{ site.data.locales[include.lang].post.button.next }}"
    >
      <p>{{ page.next.title }}</p>
    </a>
  {% else %}
    <div
      class="btn btn-outline-primary disabled"
      prompt="{{ site.data.locales[include.lang].post.button.next }}"
    >
      <p>-</p>
    </div>
  {% endif %}
</div>