.promo_slider .mob-nav { display: none; width: 100%; height: 100%; position: absolute; left: 0; top: 0; z-index: 100; }
.promo_slider .mob-bg { display: none; position: absolute; left: 0; top: 0; z-index: 1; width: 100%; height: 100%; background-position: center; background-size: cover; }

@media (max-width: 640px) {
	.promo_slider .mob-nav { display: block; }
	.promo_slider .container { position: relative; z-index: 2; }
	.promo_slider .mob-bg { display: block; }
}