Checkout extension app customize color

[HeyKK]

Hello,

I'm trying to build just simple app to display a message in checkout page using checkout UI extension and I notice that if I want to change the color of this block, It just very simple with checkout.liquid before.

But for now, we only need to stick with the components here https://shopify.dev/docs/api/checkout-ui-extensions/2023-07/components

Is there anyway I can custom like using background-color: pink or something like that?

Thank you and I'm very appreciated for your time with this question.