[j0hnik]

function resize(){
	if($(window).width() <= 768) {
		$('.advantages-item').unwrap();
	} else{
		$('.fd').wrapAll('<div class="advantages-wrap-left"></div>');
		$('.fc').wrapAll('<div class="advantages-wrap-right"></div>');
	}
}
window.matchMedia('(max-width: 768px)').addListener(function(e){
	if(e.matches) resize();
	else resize();
})
resize();

Тогда так