      <h4 class="astro-3HS6YOU4">Example : 3 columns <small class="astro-3HS6YOU4">app-side, side-visible-line, app-main</small></h4>
                  <div class="d-flex flex-row astro-3HS6YOU4">
                    <div class="astro-3HS6YOU4">
                      <pre class="astro-3HS6YOU4"><code class="astro-3HS6YOU4">&lt;div class=&quot;app-container&quot;&gt;
  &lt;aside class=&quot;app-side&quot;&gt;
    ... (not required, must be single)
  &lt;/aside&gt;
  &lt;div class=&quot;side-visible-line&quot