LayerSlider FullSize+FullWidth

Hey, i am using layerslider and created a fullsize slider. Thats fine on desktop (landscape), but not on mobile (portrait). My solution is to create 2 sliders and use one for mobile, one for desktop. But i have to make changes twice :-(
My CSS solution is quiet simple:

@media only screen and (max-width: 989px) {
#layer_slider_1 {
display: none !important;
}
}
@media only screen and (min-width: 990px) {
#layer_slider_2 {
display: none !important;
}
}

My question: is there an (CSS) solution to change the slider settings from fullsize to fullwidth depending on screen size? Goal is to use only one slider!

Thanks a lot, Sven