html, body {
    padding: 20px;
    background-color: #ffffff;
}

h1 {
    font-size: 40px;
    text-align: center;
    font-family: monospace;
}


.img {
    display: block;
    width: 50em;
    height: 20em;
    margin: 0 auto;
    margin-top: 5em;
}

@media only screen and (max-width: 900px) {

    .img { 
        width: 40em;
        height: 15em;
    }
  } 

@media only screen and (max-width: 700px) {

.img { 
    width: 30em;
}
}

@media only screen and (max-width: 550px) {

    h1 { 
        font-size: 30px; 
    }

    .img { 
        width: 20em;
        height: 10em;
    }
}

@media only screen and (max-width: 400px) {

    html{
        width: 300px;
        overflow: auto;
    }

    h1 { 
        font-size: 20px; 
    }

    .img { 
        width: 15em;
        height: 5em;
    }
}