#popup_loading {
    position:     relative;
    padding-left: 2px;
    margin-top:   40px;
}
.mail-message .mail-message-loading {
    margin-top: 100px;
}
.mail-message .progress-label,
#popup_loading .progress-label {
    position: absolute;
    left: 40%;
    font-weight: bold;
    text-shadow: 1px 1px 0 #fff;
}