div.ui-datepicker {width: 60%;}
div#my-property-calendar {margin-bottom: 20px;}
td.ui-state-error.my-highlight-dates {
    background: green !important;
    border: 1px solid green !important;
}
td.ui-state-error.my-highlight-dates a {
    background: green;
    color: #fff;
}

@media only screen and (max-width: 991px) {
    div.ui-datepicker {width: 100%;}
}
@media only screen and (max-width: 575px) {
    div.ui-datepicker {width: 500px;}
}