Change style of listings

Hello Ive just installed the plugin to test it out.

The listings that are displayed are pretty ugly and need some serious styling to look nice. One particular problem is the each listing alternates with a different color back ground.

I’ve tried to remove the alternating background colors by using firebug to find the relevant classes. None of these work.

.wpbdp-page-content{backgound-color:#000000 !important;}
.wpbdp-listing-excerpt{backgound-color:#000000 !important;}

How can I use my own custom css to style the way the listings are presented?

Thanks

https://www.ads-software.com/plugins/business-directory-plugin/