.ui-widget-overlay{
    /*background-color: rgba(255, 255, 255, 0.8);*/
    background: rgba(218, 218, 218, 0.9) !important; /* Для старых браузров */
    background: linear-gradient(to bottom, rgba(218, 218, 218, 0.8), rgba(218, 218, 218, 1)) !important;
    background: -webkit-gradient(to bottom, rgba(218, 218, 218, 0.8), rgba(218, 218, 218, 1)) !important;
    opacity: 1 !important;
}