body {
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    margin: 0;
    padding: 0;
}

header {
    background-color: #004466;
    color: white;
    padding: 1em;
    text-align: center;
}

nav {
    background-color: #0077aa;
    padding: 0.5em;
    text-align: center;
}

nav a {
    color: white;
    margin: 0 8px;
    text-decoration: none;
    font-weight: bold;
}

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

main {
    padding: 2em;
    background-color: white;
    margin: 1em auto;
    max-width: 900px;
    box-shadow: 0 0 8px rgba(0,0,0,0.1);
}

footer {
    background-color: #004466;
    color: white;
    text-align: center;
    padding: 1em;
    position: fixed;
    width: 100%;
    bottom: 0;
}