Remove Image Container Border on single page

Hello,
I’m looking for a solution to remove the image container border on a single page defined as main-content border color (see screenshot) – The border comes from the enfold main content border color setting but i’m not able to remove this for a single page and i can’t just change it in the settings cause it will affect the entire website and not only the single page

I tryed afew solutions but it seems they don’t take any effect

.page-id-9102 {
     border:none!important;
}

.page-id-9102 {
     border-color:fff!important;
}