.woocommerce-orders-table__cell-upgrade select.upgrade_courses {
    opacity: 0;
    visibility: hidden;
    height: 0;
    padding: 0;
}
/* .woocommerce-orders-table__cell-upgrade select.upgrade_courses.choose {
    opacity: 1;
    visibility: visible;
    height: 35px;
    width: 100%;
} */
.upgrade_course.hidden {
    display: none;
}
.upgrade_course {
    display: block;
}