Films With Dark Backgrounds

Hi,

Why do films like Frankenstein (2025), Sinners, Superman (2025), The Fantastic Four - First Step have a black background and coloured text across the whole of their page?

I've seen it mentioned it's possibly due to sponsorship or mobile related, but I can't see any reason why anyone would want this non-standard, difficult to read appearance. Advertisements at the top of the page I can understand, but not this.

It's quite frustrating to land on one of these pages and think that something has gone wrong with either imdb or one's browser.

Thanks