body {
    background-color: #035127;
    text-align: center;
}
body .container-plug {
    background: url(../img/Zaslepka_desktop.jpg) no-repeat center top;
    background-size: 100%;
    color: #000;
    width: 100vw;
    height: 57vw;
    max-width: 100%;
}
body .container-plug .btn-plug {
    position: absolute;
    margin-top: 54.5vw;
    display: block;
    font-size: 1.1vw;
    color: #fff;
}
@media (max-width: 768px) {
    body .container-plug {
        background: url(../img/Zaslepka_mobile.jpg) no-repeat center top;
        background-size: 100%;
        height: 190vw;
    }

    body .container-plug .btn-plug {
        margin-top: 181.5vw;
        font-size: 3.1vw;
    }
}