html,
body {
    margin: 0;
    padding: 0;
    height: 100%;
}

div.main {
    background-image: url("../img/background.jpg");
    background-size: cover;
}

p.description {
    font-family: 'Roboto', 'Open Sans', Helvetica, Arial, sans-serif;
    color: #fff;
    font-size: 4rem;
}

p.sub {
    font-family: 'Roboto', 'Open Sans', Helvetica, Arial, sans-serif;
    color: #fff;
    font-size: 1.8rem;
}

@media only screen and (max-device-width: 767px) {
    p.description {
        font-family: 'Roboto', 'Open Sans', Helvetica, Arial, sans-serif;
        color: #fff;
        font-size: 2.4rem;
    }

    p.sub {
        font-family: 'Roboto', 'Open Sans', Helvetica, Arial, sans-serif;
        color: #fff;
        font-size: 1.2rem;
    }
}