/* Default: 6 columns */
#bookslider { display: block; }
#bookslidermid { display: none; }
#bookslidersmall { display: none; }

/* Tablet: 4 columns */
@media (max-width: 1024px) { 
  #bookslider { display: none; }
  #bookslidermid { display: block; }
  #bookslidersmall { display: none; }
}

/* Mobile: 2 columns */
@media (max-width: 640px) { 
  #bookslider { display: none; }
  #bookslidermid { display: none; }
  #bookslidersmall { display: block; }
 }

/* Default: 6 columns */
#trailslider { display: block; }
#trailslidermid { display: none; }
#trailslidersmall { display: none; }

/* Tablet: 4 columns */
@media (max-width: 1024px) { 
  #trailslider { display: none; }
  #trailslidermid { display: block; }
  #trailslidersmall { display: none; }
}

/* Mobile: 2 columns */
@media (max-width: 640px) { 
  #trailslider { display: none; }
  #trailslidermid { display: none; }
  #trailslidersmall { display: block; }
 }