@media (min-width: 641px) {
    #talk_body .txt_box {
        max-width: 700px;
        padding: 0px;
        margin: 40px 0px 20px 40px;
        box-sizing: border-box;
    }
}

@media (max-width: 640px) {
    #talk_body .txt_box {
        max-width: 480px;
        padding: 0px 0px 0px 0px;
        margin: 60px 0px 20px 0px;
        box-sizing: border-box;
    }
}

@media (max-width: 640px) {
    #talk_body .txt_box .desc p:last-child {
        margin: 60px 0px 20px 0px;
    }
}

@media (min-width: 641px) {
    #talk_body .txt_box .desc p:last-child {
        margin: 60px 0px 20px 0px;
    }
}