Create "shadow border" around blog post cards

The blog post cards throughout the site I am building have white backgrounds, and the website itself is on a white background, therefore, the blog post "cards" don't stand out very well.

I could add a border from WP show posts pro, however, the border I want to add is a "shadow" border rather than a solid line around each card.

You can add borders from the plugin but there isn't a way to add a "shadow" border.

Could someone assist me with this?

I have privately added a link to a categroy page on the site I am building where you will be able to see the cards.

Thanks

Craig