* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* Body Styles */
body {
    font-family: Arial, sans-serif;
    background-color: #f8f8f8;
    color: #333;
    line-height: 1.6;
}

/* Header Styles */
header {
    background-color: #336699;
    color: white;
    padding: 20px;
    text-align: center;
}

/* Navigation Styles */
nav {
    background-color: #f0f0f0;
    padding: 10px;
    text-align: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

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

nav ul li {
    display: inline;
    margin-right: 20px;
}

nav ul li a {
    color: #336699;
    text-decoration: none;
    font-weight: bold;
}

/* Article Styles */
nav ul ul li p {
    color: #666;
    margin-top: 5px;
}

/* Horizontal Rule Styles */
hr {
    border: none;
    border-top: 1px solid #336699;
    margin: 20px 0;
}