body {
    font-family: Arial, sans-serif;
    margin: 20px;
    background-color: #ffffff;
    color: #000000;
}

header {
    background-color: #003366;
    color: white;
    padding: 15px;
}

nav {
    margin: 10px 0;
}

nav a {
    margin-right: 15px;
    color: #003366;
}

h1 {
    font-size: 24px;
}

h2 {
    font-size: 20px;
    color: #003366;
    border-bottom: 1px solid #003366;
}

h3 {
    font-size: 17px;
}

section {
    margin-bottom: 20px;
}

aside {
    background-color: #f0f0f0;
    border-left: 3px solid #003366;
    padding: 10px;
    margin: 10px 0;
}

pre {
    background-color: #f4f4f4;
    padding: 15px;
    border: 1px solid #ccc;
    overflow-x: auto;
}

code {
    font-family: "Courier New", monospace;
    color: #990000;
}

footer {
    margin-top: 20px;
    border-top: 1px solid #ccc;
    padding-top: 10px;
    font-size: 13px;
    color: #555;
}