@media (max-width: 640px) {
    #talk_body .pic {
        margin: 0 auto 5px auto;
        text-align: center;
    }
}

@media (min-width: 641px) {
    #talk_body .pic {
        margin: 0px auto 5px auto;
        text-align: center;
    }
}

@media (min-width: 641px) {
    #talk_body .txt_box {
        max-width: 700px;
        padding: 40px;
        margin: 0px auto 10px auto;
        box-sizing: border-box;
    }
}

@media (max-width: 640px) {
    #talk_body .txt_box {
        max-width: 480px;
        padding: 15px 15px 15px 15px;
        margin: calc(20 / 640 * 100vw) auto calc(20 / 640 * 100vw) auto;
        box-sizing: border-box;
    }
}