bootstrap 4 grid mixed up when using margin - php

Question

I am generating html code using php. I have some information stored in an array called $persons and I'm trying to generate a bootstrap card for each $person:
<div class="container">
<div class="row">
<?php foreach ($persons as $person): ?>
<div class="card col-md-3 m-1">
<img class="card-img-top" src="<?=person['img_src']?>" alt="<?=$person['name']?>">
<div class="card-block">
<h4 class="card-title"><?=$person['name']?></h4>
<p class="card-text"><?=$person['info']?></p>
</div>
</div>
<?php endforeach; ?>
</div>
</div>
Everything works fine when I remove m-1 class, but as soon as I add m-1 class, margin causes the last div to go to next line. I think lack of space causes this problem. How can I fix this problem? How to have margin between divs without the last div going to the next line?

Answer 1

You should have a separate div for the card since it's display:flex. Also, just use my-1 for margin-top and margin-bottom so that x-axis space is not effected...
<div class="container">
<div class="row">
<?php foreach ($persons as $person): ?>
<div class="col-md-3 my-1">
<div class="card">
<img class="card-img-top" src="<?=person['img_src']?>" alt="<?=$person['name']?>">
<div class="card-block">
<h4 class="card-title"><?=$person['name']?></h4>
<p class="card-text"><?=$person['info']?></p>
</div>
</div>
</div>
<?php endforeach; ?>
</div>
</div>
https://www.codeply.com/go/78AmkbWrLi

Answer 2

The easiest solution would be to just put another div inside the col, which applies the margin:
<div class="container">
<div class="row">
<?php foreach ($persons as $person): ?>
<div class="card col-md-3">
<div class="m-1"> <!-- NEW -->
<img class="card-img-top" src="<?=person['img_src']?>" alt="<?=$person['name']?>">
<div class="card-block">
<h4 class="card-title"><?=$person['name']?></h4>
<p class="card-text"><?=$person['info']?></p>
</div>
</div>
</div>
<?php endforeach; ?>
</div>
</div>
Or if you don't want to add another div, just add the m-1 class to the card-block.