tabler/preview/pages/_includes/cards/placeholder/card-1.html

<div class="card placeholder-glow">
	<div class="ratio ratio-21x9 card-img-top placeholder"></div>
	<div class="card-body">
		<div class="placeholder col-9 mb-3"></div>
		<div class="placeholder placeholder-xs col-10"></div>
		<div class="placeholder placeholder-xs col-11"></div>

		<div class="mt-3">
			<a href="#" tabindex="-1" class="btn btn-primary disabled placeholder col-4" aria-hidden="true"></a>
		</div>
	</div>
</div>