body {
    margin: 0;
    padding: 0;
    background: url('background.gif') no-repeat center center fixed;
    background-size: cover;
    font-family: Arial, sans-serif;
}

#header {
    text-align: center;
    padding: 20px;
    background-color: rgba(0, 0, 0, 0.7); /* Semi-transparent background for the header */
    color: #fff;
}

#nav {
    text-align: center;
    background-color: rgba(0, 0, 0, 0.7); /* Semi-transparent background for the nav */
    padding: 10px;
}

#nav a {
    color: #fff;
    margin: 0 15px;
    text-decoration: none;
    font-weight: bold;
}

#content {
    padding: 20px;
    background-color: rgba(255, 255, 255, 0.8); /* Semi-transparent background for content */
    margin: 20px;
    border-radius: 10px;
}