.pb1 {
    background: url(/assets/img/sponsors/withsecure.png) no-repeat center center;
}
.pb2 {
    background: url(/assets/img/sponsors/lloyds.png) no-repeat center center;
}
.pb3 {
    background: url(/assets/img/sponsors/adarma.png) no-repeat center center;
}
.pb4 {
    background: url(/assets/img/sponsors/ncratleos.png) no-repeat center center;
}