#ctn img {
    width: 100%;
    aspect-ratio: 1;
    border: 1px solid black;
}

@media screen and (min-width: 768px){
    #ctn {
        width: 700px;
        margin: auto;
    }

    #ctn img {
        display: block;
        width: 50%;
        margin: auto;
    }

}

h2 {
    margin: 0.5rem 0;
    font-size: 1.5rem;
}

#email {
    margin: 1rem;
    text-align: center;
}

.botoes {
    margin: 1rem;
}