ss="astro-3HS6YOU4">.app-side</code>, <code class="astro-3HS6YOU4">.side-visible-line</code>, <code class="astro-3HS6YOU4">.app-main</code> elements can be single in <code class="astro-3HS6YOU4">.app-container</code>.
                    While <code class="astro-3HS6YOU4">.app-side</code> and <code class="astro-3HS6YOU4">.side-visible-line</code> elements are
                    <u class="astro-3HS6YOU4">not required</u>, <code class="astro-3HS6YOU4">.app-main</code> is.
                  </p>

            