Changing background color of vertical /horizontal stack card or section

Hi,

I am using the new sections in HA. I noticed that the custom stack-in card is not working correctley and I wanted to ask if there is a possibility to change the background of vertical and horizontal stack, or the background of the section. The standard code is not working for the stack.
type: horizontal-stack

in the end of the day, it should look like this.

but as mentioned, the custom-stack-in card will kill the corners of the iframe-card.

It is clearly described in card-mod docs that cards without ha-card (like vertical-stack) require mod-card.

Hi,
thanks! I found a solution with sections that works for me. Maybe there will be an option in future to change the background.