td.ui-datepicker-unselectable.ui-state-disabled {
    opacity: 1;
}
td.ui-datepicker-unselectable.ui-state-disabled > .ui-state-default{
    background: #000;
    color: #FFF;
}
.ui-datepicker-other-month > span.ui-state-default {
    color: transparent !important;
}