columns center bootstrap 3

<div class="row align-items-center justify-content-center">
    <div class="col">This will be centered vertically and horizontally</div>
</div>

<!-- Center columns in a Row -->
<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>

<div class="row">
    <div class="col-md-2 col-md-offset-5"></div>
</div>