.img img {
    max-width: 500px;
}
.container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.row.gray-row  {
    background-color: #21304d;
    height: 100dvh
}
.row.err {
    display: flex;
    align-items: center;
    align-content: center;
    flex-direction: column;
    font-size: 150%;
    padding: 60px 0;
}
@media (max-width:1400px) {
    .img img {
        max-width: 369px;
    }
}

@media (max-width:991px) {
    a.main-menus {
        max-width: 80px;
        margin: auto;
        text-align: center;
        display: block;
    }

        a.main-menus img {
            width: 100%;
        }

            a.main-menus img:first-child {
                width: 70%;
                margin-bottom: 10px;
                margin-top: 20px;
            }

    .img img {
        max-width: 500px;
        width: 100%;
    }

    .img.img1 {
        display: none;
    }

    .container {
        position: relative;
        height: 100dvh;
        display: block !important;
    }

    .row.err {
        position: absolute;
        top: 100px;
        z-index: 1;
        width: calc(100% - 30px);
        padding: 40px 0 !important;
    }

        .row.err h1 {
            font-size: 90px !important;
            line-height: 0.7 !important;
        }

    .img.img2 {
        position: absolute;
        bottom: 0;
        z-index: 0;
        width: calc(100% - 30px);
    }
}
@media (max-width:499px) {
    .img img {
        max-width: 400px;
        
    }
}
@media (max-width:399px) {
 .img img {
        max-width: 300px;
        
    }
}
@media (min-width:992px) {
    .img.img2 {
        display: none;
    }
}