Hi!
I have my lightgallery opened and want before closing it 
my class only to be added when the main page is scrolled down a bit.
 

 $("#LGbest").on({
            'onBeforeOpen.lg': function(event) {
                $("body").removeClass("scrolled-down-top").addClass("scrolled-down-home");
                console.log(event.name,event);
            },
            'onBeforeClose.lg': function(event) {
                $("body").removeClass("scrolled-down-home");//add class  if scrolled down .addClass("scrolled-down-top");	 
         	console.log(event.name,event);
		
			
            }
        })
snote