I need to position slide’s background image

Hi,
I use the “Fill” fillmode for each slide of my slider. I see that all background images are centered (position center center).
I would like that some of them were “top center”, other were “bottom left”, etc. I am trying but it’s not working.

This is what I have tried. I have assigned a class to a slide, in Slides/Misc.
Example, I assigned the class “pos-bottom-left” to the first slide.

In my theme custom CSS, I added this:

.pos-bottom-left {
	background-position: bottom left !important;
}

It doesn’t do anything.

In order to check the class itself, I tried this:

.pos-bottom-left {
	border: 3px solid red !important;
	background-position: bottom left !important;
}

The red border is showing so the class itself is working. But any style concerning the background is not working.

Can you help me?

Thanks for your attention,
Fran

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