body {
    margin-top: 20px;
}

#output {
    background-color: darkslategray;
    color: white;
    font-size: 16px;
    padding: 10px;
    margin-left: auto; 
    margin-right: auto; 
    display: block;
    width: 60%;
}

#canvas {
    width: 800px;
    height: 600px;
    margin-left: auto; 
    margin-right: auto; 
    display: block;
}