.Previous
{
    height:40px;
    width:40px;
    background-image:url("/Sitefinity/WebsiteTemplates/UFSTemplate2017/App_Themes/UFSTemplate/Images/prev.jpg");
}

.Next
{
    height:40px;
    width:40px;
    background-image:url("/Sitefinity/WebsiteTemplates/UFSTemplate2017/App_Themes/UFSTemplate/Images/next.jpg");
}