{# 🧬 기술 계보 partial (ARG-159). Rendered inside item_detail.html only when
   `item.predecessors` or `item.successors` is non-empty. #}
{% if item.predecessors or item.successors %}
<section class="detail-genealogy">
  <h2 class="detail-section__title">🧬 기술 계보</h2>

  {% if item.predecessors %}
  <div class="genealogy-group">
    <h3 class="genealogy-group__label">선행</h3>
    <ul class="genealogy-list">
      {% for entry in item.predecessors %}
      <li class="genealogy-entry">
        <span class="genealogy-relation genealogy-relation--{{ entry.relation_type.value|lower }}">{{ entry.relation_type.value }}</span>
        <a class="genealogy-link" href="/item/{{ entry.tech_id }}">{{ entry.title }}</a>
        {% if entry.reasoning %}
        <p class="genealogy-reasoning">{{ entry.reasoning }}</p>
        {% endif %}
      </li>
      {% endfor %}
    </ul>
  </div>
  {% endif %}

  {% if item.successors %}
  <div class="genealogy-group">
    <h3 class="genealogy-group__label">후속</h3>
    <ul class="genealogy-list">
      {% for entry in item.successors %}
      <li class="genealogy-entry">
        <span class="genealogy-relation genealogy-relation--{{ entry.relation_type.value|lower }}">{{ entry.relation_type.value }}</span>
        <a class="genealogy-link" href="/item/{{ entry.tech_id }}">{{ entry.title }}</a>
        {% if entry.reasoning %}
        <p class="genealogy-reasoning">{{ entry.reasoning }}</p>
        {% endif %}
      </li>
      {% endfor %}
    </ul>
  </div>
  {% endif %}
</section>
{% endif %}