.page-header .phd-logo{
    color: transparent;
    display: block;
    height: 30px;
    text-indent: -99em;
    width: 140px;
}
.page-header .phd-logo{
    width: 130px;
}
.phd-logo {
    background-image: url("image/logo.png");
    background-size: 100% 100%;
    color: transparent;
}