<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css"> <script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script> <script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script> <!------ Include the above in your HEAD tag ----------> <div class="container main"> <h2 class="text-center">Grid Banner</h2> <hr> <div class="row"> <div class="col-sm-6"> <img src="http://placehold.it/600x400" alt="" class="img-responsive center-block"> </div> <div class="row col-sm-6"> <div class="col-xs-6"> <img src="http://placehold.it/300x205" alt="" class="img-responsive"> </div> <div class="col-xs-6"> <img src="http://placehold.it/300x205" alt="" class="img-responsive"> </div> <div class="col-xs-6"> <img src="http://placehold.it/300x205" alt="" class="img-responsive"> </div> <div class="col-xs-6"> <img src="http://placehold.it/300x205" alt="" class="img-responsive"> </div> </div> </div> </div>

.main .img-responsive { margin-bottom: 30px; }