Getting rid of a black background in the 980 px zone

Hi,
I want to put a very dark backgroung on all my pages, even where there is text (that’s almost white).
I turn all the sections backgrounds to transparent but the 980 px width central zone remains black when I do that and my dark background only shows on the sides (plus I prefer adding content on more than 980 px, have checked how the website looks on various devices and it’s fine).
I thought Wix wouldn’t allow it to be certain my text could be read but it turns out that I can use the same background color as the text color and then the background even goes behind the 980 px zone and you can’t see the text…

How can I get rid of that black 980 px width background?
Thanks for your help,
Kind regards, Fanny

Have you used layers panel?
Sometimes you need to change the “page” element’s color and such as cells too since you’re using cell inside the section.