Adding Klarna "buy now, pay later with link" in custom liquid to product page

[Kingstone]

I see many shopify stores have this “Buy now, pay within 30 days with Klarna. Read more”

You can se on this website: Premium Key N214 | Thule | Sverige

I tried to copy this code:

And everything looks the same but nothing happen when i pres on the “Läs mer”

Shoppa nu. Betala inom 30 dagar med Klarna. 

Do i need to create something in css or something in the code?

[suyash1]

@Kingstone - it does not work due to html, please add klarna app