li.societies a {background-image: url(activities_main01.jpg);}
li.sports a {background-image: url(activities_main02.jpg);}

li.facilities a {background-image: url(activities_upperleft.jpg);}
li.opportunities a {background-image: url(activities_upperright.jpg);}
li.contacts a {background-image: url(activities_lowerleft.jpg);}
li.volunteering a {background-image: url(activities_lowerright.jpg);}