Better to use
$xf.style.style_id
, which will give you the ID of the current style. Using
$xf.visitor.style_id
only gives you the preference, which for the vast majority of users (and all guests) will be
0
(which means to use the default style).
Edit: I think it works now. I had to add "$xf.visitor.style_id == 69 OR !$xf.visitor.style_id == 69" for the Dark navigation.
This probably doesn't work the way you expect (or if it does, it's merely incidental). If you wanted to check if the ID was
not 69
, you'd use
$xf.style.style_id != 69
.