Overwrite injected CSS from AdBlock

my site displays a buy link which is affiliated with the Awin affiliation program. Awin links are blocked by AdBlock Plus via this CSS which is injected by the extension :

a[href^="https://www.awin1.com/cread.php?"] {
    display: none!important;
}

I tried to overwrite that with Javascript by detecting if the user is using AdBlock : in that case I add a .ab class to the and tags and and declares this CSS rule inmy stylesheet :

html.ab {
    a[href^="https://www.awin1.com/cread.php?"].ab {
        display: block!important;
    }
}

But this does not work. Does injected CSS by extensions take precedence over the app's stylesheet, whatever my rules ?

thanks