evolve plus theme banner image

I have LayerSlider presenting in the banner image area on the home page of an evolve plus themed site. There appears to be a background of the banner and it appears to be 370 pixels. My LayerSlider is 345 pixels high. How do I reduce the size of the background area to allow the LayerSlider to appear with no grey area at the bottom? site is http://livingwaterunity.org

thanks in advance for your help!