<?php while (have_posts()) : the_post();
	/* grab the url for the full size featured image */
	$featured_img_url = get_the_post_thumbnail_url(get_the_ID(),'full');

/* Background Image as a div bg. */
	echo '<div class="featuredImage" style="background-mage:url('.esc_url($featured_img_url).');"></div>';
        ?>

    <?php endwhile; ?>