.main {
    display: none;
}

.adjust_Hpadding {
    padding: 0px;
}
@media (min-width: 768px) {
    .main {
        display: block;
        margin-left: auto;
        margin-right: auto;
        width: 40%;
    }

    .adjust_Hpadding {
        padding: 20px;
    }
}