CSS noob need help

[maladath 0]

Hi guys, can someone teach me how can I resize height of a thumb use CSS?

Many thanks and have a nice day!

[Happy2Play 9780]

You would adjust the backdropcard.

I use this, but note it affect all backdropcards.

@media (min-width: 100em)
{.backdropCard {
    width: 15vw;
}}