.confLogoBox {
    width: 100vw;
    position: relative;
    text-align: center;
    float: none;
}
@media screen and (min-width: 950px) {
    .confLogoBox {
        margin: 0 0 0 -50vw;
        left: 50%;
    }
}
.confLogoBox img {
    max-width: 100%;
}