body {
            font-family: Arial, sans-serif;
            line-height: 1.6;
            margin: 0;
            padding: 0;
            color: #333;
            background-color: #f5f5f5;
        }
        header {
            background-color: #003366;
            color: white;
            padding: 1rem;
            text-align: center;
            position: relative;
        }
        .logo {
            font-size: 2rem;
            font-weight: bold;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
        }
        nav {
            display: flex;
            justify-content: space-around;
            flex-wrap: wrap;
            margin-top: 1rem;
        }
        nav a {
            color: white;
            text-decoration: none;
            padding: 0.5rem 1rem;
            border-radius: 5px;
            transition: background-color 0.3s;
        }
        nav a:hover {
            background-color: #0055aa;
        }
        .mobile-nav-toggle {
            display: none;
            position: absolute;
            top: 1rem;
            right: 1rem;
            background: none;
            border: none;
            color: white;
            font-size: 1.5rem;
            cursor: pointer;
        }
        @media (max-width: 768px) {
            .mobile-nav-toggle {
                display: block;
            }
            nav {
                display: none;
                flex-direction: column;
                width: 100%;
            }
            nav.active {
                display: flex;
            }
        }
        main {
            padding: 2rem;
            max-width: 1200px;
            margin: 0 auto;
            background-color: white;
            box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
        }
        h1, h2, h3 {
            color: #003366;
        }
        h1 {
            font-size: 2.5rem;
            margin-bottom: 1.5rem;
            text-align: center;
        }
        h2 {
            font-size: 2rem;
            margin-top: 2rem;
            border-bottom: 2px solid #003366;
            padding-bottom: 0.5rem;
        }
        h3 {
            font-size: 1.5rem;
            margin-top: 1.5rem;
        }
        p {
            margin-bottom: 1rem;
        }
        .download-btn, .login-btn {
            display: inline-block;
            background-color: #00aa55;
            color: white;
            padding: 0.8rem 1.5rem;
            text-decoration: none;
            border-radius: 5px;
            margin: 1rem 0;
            transition: background-color 0.3s;
        }
        .download-btn:hover, .login-btn:hover {
            background-color: #008844;
        }
        .image-container {
            text-align: center;
            margin: 2rem 0;
        }
        .image-container img {
            max-width: 100%;
            height: auto;
            border-radius: 5px;
        }
        .table-of-contents {
            background-color: #f0f0f0;
            padding: 1rem;
            border-radius: 5px;
            margin-bottom: 2rem;
        }
        .table-of-contents h3 {
            margin-top: 0;
        }
        .table-of-contents ul {
            list-style-type: none;
            padding-left: 0;
        }
        .table-of-contents li {
            margin-bottom: 0.5rem;
        }
        .table-of-contents a {
            color: #003366;
            text-decoration: none;
        }
        .table-of-contents a:hover {
            text-decoration: underline;
        }
        footer {
            background-color: #003366;
            color: white;
            text-align: center;
            padding: 1rem;
            margin-top: 2rem;
        }
        footer a {
            color: white;
            text-decoration: none;
        }
        footer a:hover {
            text-decoration: underline;
        }
        .tags {
            margin-top: 2rem;
        }
        .tags a {
            display: inline-block;
            background-color: #e0e0e0;
            color: #333;
            padding: 0.3rem 0.8rem;
            margin-right: 0.5rem;
            margin-bottom: 0.5rem;
            border-radius: 5px;
            text-decoration: none;
        }
        .tags a:hover {
            background-color: #d0d0d0;
        }