bootstrap d-flex center code example

Example 1: bootstrap justify-content-center for md

<div class="row justify-content-md-center"></div>

Example 2: alighn right boostrap 4

<div class="float-left">Float left on all viewport sizes</div><br>
<div class="float-right">Float right on all viewport sizes</div><br>
<div class="float-none">Don't float on all viewport sizes</div>