.form-group {
    max-width: 250px;
}
.input-group-addon {
	background-color: #EEEEEE;
    background-image: url(http://caron.ads.intra.inist.fr:53390/img/istex-logo.svg);
    background-repeat: no-repeat;
    background-position: center;
    background-size: 100%;
}
.loading {
    height: 16px;
}