mix-blend-mode and mobile menu

Hi I had this working a while back but accidentally deleted the code. To get it working it used a :not tag in css. However, whatever I target I can't get it to work.

I'm trying to have the mix-blend-mode of difference on my menu at all time expect for when the menu is open in mobile.

Could anyone remind me what I need to target?

It was something like

.header:not(.header-menu-bkg) {
mix-blend-mode: difference;
}

But I can't get it to work. I know it's something very simple.

mrwatt.co.uk for ref

6 hours ago, jaeveedee said:

@mrpowerSee this thread, im pretty sure this solves your issue too.
 

 

Thats the topic I've been searching for all day. thanks!!!