body {
    font-family: Arial, sans-serif;
    line-height: 1.6;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.container {
    display: flex;
    flex: 1;
}

header {
    background-color: #333;
    color: #fff;
    text-align: center;
    padding: 1rem;
}

nav {
    background-color: #f4f4f4;
    padding: 20px;
    width: 200px;
}

nav ul {
    list-style-type: none;
    padding: 0;
}

nav ul li {
    margin-bottom: 10px;
}

nav ul li a {
    color: #333;
    text-decoration: none;
}

nav ul li a:hover {
    text-decoration: underline;
}

main {
    flex: 1;
    padding: 20px;
    background-color: #fff;
}

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

.back-link {
    display: inline-block;
    margin-top: 20px;
}

@media (max-width: 768px) {
    .container {
        flex-direction: column;
    }

    nav {
        width: 100%;
        order: -1;
    }
}