{#
  Single blog card. Rendered once per PostSummary in the home-page loop.

  Expects the loop variable `post` in scope with:
    - post.slug          (str)
    - post.title         (str)
    - post.published_at  (datetime)
    - post.excerpt       (str)

  The post detail page does not exist yet (Phase 2 adds it), but we link
  to /posts/<slug> anyway so the card markup is final. Phase 2 will
  register the route; until then the link 404s, which is acceptable
  because the post list itself is empty in Phase 1.
#}
<article class="post-card">
  <header class="post-card__header">
    <h2 class="post-card__title">
      <a href="/posts/{{ post.slug }}">{{ post.title }}</a>
    </h2>
    <time class="post-card__date"
          datetime="{{ post.published_at.isoformat() }}">
      {{ post.published_at.strftime("%B %-d, %Y") }}
    </time>
  </header>
  <p class="post-card__excerpt">{{ post.excerpt }}</p>
</article>