body {
    width: 80%;
    font-family: Arial, sans-serif;
    margin: auto;
    padding: 0;
    background-color: #f9f9f9;
    color: #333;
}

header {
    background-color: #18a33c;
    color: white;
    text-align: center;
    padding: 20px 10px;
}

nav ul {
    list-style: none;
    margin: 0;
    padding: 10px;
    background-color: #34495e;
    text-align: center;
}

nav ul li {
    display: inline;
    margin: 0 10px;
}

nav ul li a {
    align-content: center;
    color: white;
    text-decoration: none;
}

main {
    padding: 20px;
}

main img {
    max-width: 100%;
    height: auto;
    display: block;
    margin: 10px auto;
}

footer {
    background-color: #7f8c8d;
    color: white;
    text-align: center;
    padding: 10px;
    margin-top: 20px;
}