I have this code on the header of my site:

<?php if(($Variable1 > 0) && (isset($_SESSION["role"]) && ($_SESSION["role"]==12 || $_SESSION["role"]==13))){ ?>
            <button type="button" class="btn btn-danger btn-block btn-block"><i class="fa fa-exclamation-triangle">
            </i> Number Left: <?php echo $NumberLeft; ?></button>
            <?php } ?>

I want this code to run every 30 seconds.

I can't make a page refresh every 30 seconds because I would lose the data that is not saved until then in that page. So I need to refresh only the specific banner. I found by searching I could refresh the header

(header('Refresh: 10; URL=http://yoursite.com/page.php');

but it's refreshing the whole page, which I do not want. Also, I would like this header-refresh to happen on all pages on the site since this header is common.