.BoxContainer {
    display: flex; /* or inline-flex */
    flex-direction: row;
    flex-wrap: wrap;
}

.Box {
    background-color: #ffffff;
    height: 400px;
    width: 400px;
    margin: 5px;
    position: relative;
    user-select: none;
}

.BoxButton {
    background-color: #ffffff;
    height: 400px;
    width: 400px;
    margin: 5px;
    position: relative;
    user-select: none;
    cursor: pointer;
}

@media (max-width: 767.98px) {
    .Box {
        width: 100%;
    }

    .BoxButton {
        width: 100%;
    }
}