body {
    background-size: cover;
    background-attachment: fixed;
    background-image: 
        linear-gradient(
                rgba(120, 80, 150, .75),
                rgba(120, 80, 150, .75)
        ), 
        url("../img/tunnel.jpg");
}

#divQuote {
    display: none;
    color: white;
    margin: 25% auto 0;
    text-align: center;
}

#divButton {
    margin: 20px auto 0;
    text-align: center;
}

#divTweet {
    margin: 20px auto 0;
    text-align: center;
}

#divTweet a {
    color: #fff;
}

button {
    cursor: pointer;
    border-radius: 50%;
    width: 70px;
    height: 70px;
    border: 1px solid #888;
    background-image:
        linear-gradient(
            rgba(120, 80, 150, .15),
            rgba(120, 80, 150, .15)
        );
}

button:focus {
  outline: none;
}