@media (max-width:800px) {
.header_text {
    right:0;
    top:0;
    position:relative;
    margin-top:30px;
    margin-right:auto;
    margin-left:auto;
    text-align:center;
}
.navi_top {
    display:none;
}
.nav_mobile {
    display:block;
        margin-right:auto;
        margin-left:auto;
        text-align:center;
}
.nav_mobile a {
    display:block;
        font-size:30px;
        line-height:40px;
        color:#ffffff;
}
}