How can I achieve better PDF embeds with HTML and CSS? or What’s the best way to create better PDF em

For a custom preview, you could convert the first page of the PDF to an image (using something like CloudConvert) and then swap it out for the full PDF when clicked.

Adds a bit of overhead, but it’s a nice UX touch.

For better pdf embeds html css, I’d say focus on the container styling—padding, shadows, etc.—to make it feel native to your site.