col-md-3 lines are not proper
<div id="mysection">
<div class="container">
<div class="row">
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
<div class="col-md-3 equal-column"></div>
</div>
</div>
</div>
Add CSS:
.equal-column{min-height:300px;}