img{
    max-width: 100%;
}


body{
    margin-left: auto;
    margin-right: auto;
    width:90%;
    max-width: 40rem;
}

html{font-size: 12pt;}

    @media(min-width:640x) {
        html{font-size:16pt;}
    }

@media (min-width:640px){
    .two-columns-example{
        display:flex;
    }
    
    .two-columns-example > * {
        width:50%;
    }
}