html {
    background: url(bg.jpg) no-repeat center center fixed;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}

.textarea {
    margin: 0;
    position: absolute;
    top: 30%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: xx-large;
    font-weight: bold;
    font-family: fantasy;
}