Masonry layout with Bootstrap – grid cloumns

If You would like to implement only the masonry component of bootstrap

//CARD COLUMNS
.card-columns .card {
  margin-bottom: 0.75rem;
}

@media (min-width: 576px) {
  .card-columns {
    -webkit-column-count: 3;
    -moz-column-count: 3;
    column-count: 3;
    -webkit-column-gap: 1.25rem;
    -moz-column-gap: 1.25rem;
    column-gap: 1.25rem;
    orphans: 1;
    widows: 1;
  }
  .card-columns .card {
    display: inline-block;
    width: 100%;
  }
}

HTML structure with WordPress loop

<?php
wp_reset_postdata();
  
$args = array(
    'post_type' => 'post_type',
    'posts_per_page' => -1
);
  
$the_query = new WP_Query( $args ); ?>
 
    <div class="card-columns">
        
        <?php if ( $the_query->have_posts() ) : while ( $the_query->have_posts() ) : $the_query->the_post(); ?>
     
           <div class="card">
                
                <!---->
               
            </div>
 
        <?php endwhile; endif; ?>
    </div>
 
<?php wp_reset_postdata(); ?>