{% load render_table from django_tables2 %}
<div class="card">
  <h2 class="card-header">Connected Structures</h2>
  {% if connected_structures_table.rows|length %}
    {% render_table connected_structures_table 'inc/table.html' %}
  {% else %}
    <div class="card-body text-muted">No directly connected structures.</div>
  {% endif %}
</div>