body, html {
    height: 100%;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    align-items: center; /* horizontal centering */
    justify-content: flex-start; /* vertical alignment from top */
    font-family: sans-serif;
    background-color: #f5f5f5;
}

#toolbar {
    margin: 10px 0;
}

#paper {
    width: 800px;
    height: 600px;
    border: 1px solid #999;
    background-color: #ffffff;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

#instructions {
    max-width: 800px;
    margin: 20px auto;
    padding: 15px;
    background-color: #f9f9f9;
    border: 1px solid #ccc;
    border-radius: 8px;
    font-size: 14px;
    line-height: 1.5;
}

#instructions h3 {
    margin-top: 0;
}

#instructions code {
    background-color: #eee;
    padding: 2px 4px;
    border-radius: 3px;
}