bootstrap 4 accordion open from bottom code example
Example: open one accordion at a time bootstrap
Notice that each panel has a data-parent which targets the parent div with the
ID #panels.
<div class="panel-group" id="panels">
<div class="panel panel-default">
<div class="collapsed" data-toggle="collapse" data-parent="#panels" data-target="#firstPanel">
<h4>First header</h4>
</div>
<div id="firstPanel" class="panel-collapse collapse">
<div>Content.</div>
</div>
</div>
<div class="panel panel-default">
<div class="collapsed" data-toggle="collapse" data-parent="#panels" data-target="#secondPanel">
<h4>Second header</h4>
</div>
<div id="secondPanel" class="panel-collapse collapse">
<div>Other content.</div>
</div>
</div>
</div>