body .MainContents {
    margin: 40px auto;
}
@media screen and (max-width: 764px) { 
    body .MainContents {
        margin: 0 0 40px;
        padding: 20px;
        background: #fff;
    }
}

.MainContents .title {
    font-size: 180%;
    margin-bottom: 40px;
}
.MainContents .textbody {
    font-size: 16px;
    line-height: 1.6;
}