bs4 column structure code example
Example: Bootstrap 4 Grid
<!-- Control the column width, and how they should appear on different devices -->
<div class="row">
<div class="col-*-*"></div>
<div class="col-*-*"></div>
</div>
<div class="row">
<div class="col-*-*"></div>
<div class="col-*-*"></div>
<div class="col-*-*"></div>
</div>
<!-- Or let Bootstrap automatically handle the layout -->
<div class="row">
<div class="col"></div>
<div class="col"></div>
<div class="col"></div>
</div>