#mainImg {
    background: linear-gradient(55deg, #f9e258 50%, transparent 50%), url("../contact/img/bg_main.jpg");
}

#contents .oneWord {
    font-size: 110%;
    line-height: 1.2;
    margin-top: 20px;
}
#contents h3 {
    font-size: max(22pt, 2vw);
    font-weight: normal;
    margin-bottom: .5em;
}

#contents .form > dl > div {
    display: flex;
    gap: 1em;
    margin-bottom: 1em;
}
#contents .form > dl > div dt {
    width: 18em;
}
#contents .form > dl > div dd {
    flex: 1;
}

#contents form .btnBox .btn {
    font-size: 110%;
    padding: 10px 1.5em;
}
#contents form .btnBox .btn.back {
    border-color: #999;
    background-color: #999;
}
#contents form .btnBox .btn.back:hover {
    color: #999;
    background-color: #fff;
}

@media screen and (max-width: 430px){
    #contents h3 {
        line-height: 1.2;
    }
    #contents .oneWord {
        margin-bottom: 10px;
    }
    #contents .form .btnBox dd {
        text-align: center;
    }
    #contents .form .btnBox dd button {
        margin-bottom: 1.5em;
    }
    #contents .form .btnBox .btn {
        width: 100%;
    }
    #contents .form input,
    #contents .form select,
    #contents .form textarea
    {
        font-size: 95%;
    }
}