I'm still puzzled about when to separate my items using a grid system and columns, and when to utilize d-flex. Picture this scenario with 4 buttons:
<link href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<div class="d-flex justify-content-center">
<button class="btn">First</button>
<button class="btn">second</button>
<button class="btn">Third</button>
<button class="btn">fourth</button>
<button class="btn">Fifth</button>
<button class="btn">six</button>
</div>
When I have items in a row that need to be centered without any space between them, how can I achieve this? Should I opt for col and row or flex?