bootstrap 4 align middle code example
Example 1: bootstrap 4 center div
<div class="d-flex justify-content-start">...</div>
<div class="d-flex justify-content-end">...</div>
<div class="d-flex justify-content-center">...</div>
<div class="d-flex justify-content-between">...</div>
<div class="d-flex justify-content-around">...</div>
Example 2: bootstrap center align columns
<div class="row d-flex justify-content-center text-center">
<div class="col-4">
// Add Content
</div>
<div class="col-4">
// Add Content
</div>
<div class="col-4">
// Add Content
</div>
</div>