how to change mouse-over effect

Hi Support,

how are we able to change our mouse-over effect? At the moment we have a dark grey mouseovereffect (like here: http://www.digitale-innovation.de/use-cases/) and we want to change it to a white one like in this demo: https://hb-themes.com/themes/highend_wp/blog-carousel/

Can we change it in the themes options? Or which css code do we need to change it.