.mce-menu-item.mce-menu-item-preview.mce-active .mce-text,
.mce-menu-item.mce-menu-item-preview.mce-active .mce-ico {
    color: #FFF !important;
}

.mce-menu-item.mce-menu-item-preview.mce-active {
    border-left: 5px solid #2271b1 !important;
}