<div class="d-inline-flex bg-primary">d-inline-flex</div>
<span class="d-sm-inline-flex bg-primary">d-sm-inline-flex</span>
<span class="d-md-inline-flex bg-primary">d-md-inline-flex</span>
<span class="d-lg-inline-flex bg-primary">d-lg-inline-flex</span>
<span class="d-xl-inline-flex bg-primary">d-xl-inline-flex</span>
You don't need to remember all CSS classes. Just use the Bootstrap Editor instead.