Banner Diferenciado

<script type="text/javascript" charset="utf-8">
/* agenciaekos.com.br */
      $('.banner.cheio .slides>li').each(function(){
    console.log($('>a>img', this).attr('alt'));
    if($('>a>img', this).attr('alt').indexOf("mobile")!=-1) {
        $(this).addClass('banner-mobile');
        if(screen.width > 540){
           $('.banner-mobile').remove();
        }
    }else{
        $(this).addClass('banner-desktop');
        if(screen.width <= 540){
           $('.banner-desktop').remove();
        }
    }
});
    </script>