docs/includes/guide-card.html

{% if guide.page.authors %}
  {% assign authors = guide.page.authors %}
{% else %}
  {% assign authors = 'GitHub' | split: ' ' %}
{% endif %}
{% assign authorsString = authors | join: ", @" %}

<div class="col-lg-4 col-12 mb-3">
  <a class="Box color-shadow-medium height-full d-block hover-shadow-large no-underline color-text-primary p-5" href="{{ guide.href }}">
    <h2>{{ guide.title }}</h2>
    <p class="mt-2 mb-4 color-text-tertiary">{{ guide.intro }}</p>

    <footer class="d-flex">
      <div class="mr-1">
        {% if authors.length == 1 %}
          <img class="avatar avatar-2 circle mr-1" src="https://github.com/{{ authors[0] }}.png" alt="@{{ authors[0] }}" />
        {% else %}
          <div class="AvatarStack AvatarStack--three-plus">
            <div
              class="AvatarStack-body tooltipped tooltipped-se tooltipped-align-left-1"
              aria-label="@{{ authorsString }}"
            >
              {% for author in authors %}
                <img
                  class="avatar circle"
                  alt="@{{ author }}"
                  src="https://github.com/{{ author }}.png"
                />
              {% endfor %}
            </div>
          </div>
        {% endif %}
      </div>

      <div>
        @{{ authorsString }}
      </div>
    </footer>
  </a>
</div>