Gallery has some kind of overlay - png is not fully transparent

Hello, There is some kind of overlay on the gallery block that makes png images not fully transparent. See screenshot - a the gallery container shows a box with some kind of overlay. I'll also attach the png image so you can see it is fully transparent.

This is a super common issue but I can't find the solution for GALLERY BLOCKS on the FLUID ENGINE.

I've gone through the styles for the whole website and set all "overlays" to transparent but it doesn't help.

How to remove this overlay? Site is not paid/published yet for client, but screenshot is attached - should be clear what the issue is.

I remember solving once before, a few versions ago, but can't remember how!

Thanks for your help.

I think it's beside the point, but I know it's not best practice to put text into images, but the client wants a slideshow series of text over a static background - any other ideas of how to do this feel free to shout it out 🙂

ok, we’ve gone with a different solution so this is no longer a real issue, just a curiosity! Here’s the problematic gallery in action: https://www.participantenergy.com/home-alternate

I Believe there is no gallery block style setting, but so many other settings for blocks.. maybe this is coming later!