Applying margins to the columns in Bootstrap may disrupt the grid layout. The spacing between columns is achieved using padding, so it's recommended to place an additional container or box inside each column for any shadow effects. Adjust the padding of the columns as needed:
<div class="row">
<div class="col-md-4 col-sm-6 text-center feature-item rounded py-3">
<div class="shadow">
<div class="feature-icon pb-3">
<i class="fa fa-piggy-bank"></i>
</div>
<div class="">
<h4 class="">Unique title.</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>
</div>
<!--//content-->
</div>
</div>
<!--//item-->
<div class="col-md-4 col-sm-6 text-center feature-item rounded py-3">
<div class="shadow">
<div class="feature-icon pb-3">
<i class="fa fa-piggy-bank"></i>
</div>
<div class="">
<h4 class="">Another unique title.</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>
</div>
<!--//content-->
</div>
</div>
<!--//item-->
<div class="col-md-4 col-sm-6 text-center feature-item rounded py-3">
<div class="shadow">
<div class="feature-icon pb-3">
<i class="fa fa-piggy-bank"></i>
</div>
<div class="">
<h4 class="">One more unique title.</h4>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit.</p>
</div>
<!--//content-->
</div>
</div>
<!--//item-->
</div>
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