body {
    background-color: #f5f5f5;
    color: #333333;
    font-family: Arial, Helvetica, sans-serif;
    margin: 10px;
}

header {
    background-color: #333333;
    color: #ffffff;
    padding: 20px;
    margin-bottom: 0;
}

h1 {
    text-align: center;
    margin-top: 0;
    margin-bottom: 0;
    color: #ffffff;
}

h2 {
    margin-top: 30px;
    margin-bottom: 15px;
}

nav {
    text-align: center;
    margin-top: 0;
    margin-bottom: 30px;
    padding: 15px;
    background-color: #444444;
}

nav a {
    color: #ffffff;
    padding: 5px 10px;
    margin: 0 5px;
}

nav a:hover {
    background-color: #555555;
    text-decoration: none;
}

main {
    max-width: 800px;
    margin: 20px auto;
    padding: 20px;
    background-color: #ffffff;
    line-height: 1.6;
}

p {
    margin-bottom: 15px;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 20px auto;
}

figure {
    text-align: center;
    margin: 20px 0;
}

figcaption {
    margin-top: 10px;
    font-style: italic;
    color: #666666;
}

audio {
    display: block;
    margin: 20px auto;
    width: 100%;
    max-width: 500px;
}

iframe {
    display: block;
    margin: 20px auto;
}

a {
    color: #0066cc;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

footer {
    text-align: center;
    font-size: 0.9em;
    margin-top: 40px;
    padding: 20px;
    color: #666666;
}

iframe {
    border: none;
}