.wpcf7-form label.error
{
    color: #fff;
    font-size: 11px;
    float: none;
    padding-left: 5px;
}
.noErrorMsg.wpcf7-form label.error
{
    display: none!important;
    height: 0!important;
    width: 0!important;
    overflow: hidden!important;
}
strong.invalid
{
    color: #f00;
}
strong.valid
{
    color: #008000;
}