#header.ja {
    top: 0;
    padding: 12px 0;
}

#header.ja .logo {
    text-align: center;
}
#header.ja img {
    width: revert-layer;
}

.link_to_official_site {
    position: absolute;
    top: 47px;
    z-index: 1;
}
@media screen and (max-width: 768px) {
    .link_to_official_site {
        text-align: center;
        background-color: #fff;
        border: solid #d7d7d7;
        border-width: 1px 0;
        width: 100%;
        padding: 8px 0;
    }
}
@media screen and (min-width: 769px) {
    .link_to_official_site {
        position: fixed;
        right: 20px;
        top: 0;
        font-size: 1.3rem;
        line-height: 60px;
        z-index: 9999;
    }
}