@media screen and (max-width: 600px){
    body{
        margin: 0;
        background: white;
    }

    .card{
        padding: 0;
        margin: 0;
        border-radius: 0;
        box-shadow: none;
    }
    .topo{
        border-radius: 0;
        width: 100%;
    }
    section{
        margin: 40px;
    }
}