@media (max-width: 700px) {
    html {
        /*font-size: calc(20px + 5vw);*/
        font-size: 3vw;
    }

    section, #msg_acc {
        width: 95%;
    }

    #msg_acc, footer {
        padding: 50px 5vw;
    }

    #boxjaune {
        margin: 40px auto 0 auto;
        width: 95%;
    }

    footer {
        width: unset;
    }
}