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

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            line-height: 1.6;
            color: #333;
            background-color: #f8f9fa;
        }

        header {
            background-color: #fff;
            padding: 1.5rem 0;
            box-shadow: 0 2px 4px rgba(0,0,0,0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        .logo-container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 2rem;
            text-align: center;
        }

        nav {
            background-color: #4a90e2;
            padding: 0;
        }

        nav ul {
            list-style: none;
            display: flex;
            justify-content: center;
            max-width: 1200px;
            margin: 0 auto;
            flex-wrap: wrap;
        }

        nav ul li {
            margin: 0;
        }

        nav ul li a {
            display: block;
            padding: 1rem 2rem;
            color: #fff;
            text-decoration: none;
            transition: background-color 0.3s ease;
        }

        nav ul li a:hover,
        nav ul li a.active {
            background-color: #357abd;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 2rem;
        }

        .title {
            background-color: #4a90e2;
            color: #fff;
            padding: 2rem;
            margin: 2rem 0;
            border-radius: 8px;
        }

        h1 {
            font-size: 2.5rem;
            margin-bottom: 0.5rem;
            font-weight: 700;
        }

        .back-link {
            color: #fff;
            text-decoration: none;
            font-size: 0.95rem;
            opacity: 0.9;
            transition: opacity 0.3s ease;
        }

        .back-link:hover {
            opacity: 1;
            text-decoration: underline;
        }

        article {
            background-color: #fff;
            padding: 3rem;
            margin: 2rem 0;
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.1);
        }

        article h2 {
            font-size: 2rem;
            margin: 2rem 0 1rem;
            color: #2c3e50;
        }

        article h3 {
            font-size: 1.5rem;
            margin: 1.5rem 0 0.75rem;
            color: #34495e;
        }

        article h4 {
            font-size: 1.25rem;
            margin: 1.25rem 0 0.5rem;
            color: #34495e;
        }

        article p {
            margin-bottom: 1.25rem;
            font-size: 1.05rem;
            color: #555;
        }

        .transition-section {
            background-color: #fff;
            padding: 2.5rem 3rem;
            margin: 2rem 0;
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.1);
        }

        .transition-section p {
            font-size: 1.05rem;
            color: #555;
            margin-bottom: 1.25rem;
        }

        .links-section {
            background-color: #fff;
            padding: 3rem;
            margin: 2rem 0;
            border-radius: 8px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.1);
        }

        .links-section h3 {
            font-size: 1.75rem;
            margin-bottom: 1.5rem;
            color: #2c3e50;
            padding-bottom: 0.75rem;
            border-bottom: 3px solid #4a90e2;
        }

        .links-section ul {
            list-style: none;
            column-count: 2;
            column-gap: 3rem;
            margin-bottom: 2.5rem;
        }

        .links-section ul li {
            margin-bottom: 0.75rem;
            break-inside: avoid;
        }

        .links-section ul li a {
            color: #4a90e2;
            text-decoration: none;
            font-size: 1.05rem;
            transition: color 0.3s ease;
            display: inline-block;
            padding: 0.25rem 0;
        }

        .links-section ul li a:hover {
            color: #357abd;
            text-decoration: underline;
        }

        footer {
            background-color: #2c3e50;
            color: #ecf0f1;
            text-align: center;
            padding: 2.5rem 2rem;
            margin-top: 4rem;
        }

        footer p {
            margin-bottom: 1rem;
            line-height: 1.8;
        }

        hr {
            border: none;
            border-top: 1px solid #e0e0e0;
            margin: 2rem 0;
        }

        @media (max-width: 768px) {
            h1 {
                font-size: 2rem;
            }

            nav ul {
                flex-direction: column;
            }

            nav ul li a {
                padding: 0.75rem 1rem;
                border-bottom: 1px solid rgba(255,255,255,0.1);
            }

            article {
                padding: 2rem 1.5rem;
            }

            .container {
                padding: 1rem;
            }

            .title {
                padding: 1.5rem;
            }

            .transition-section {
                padding: 1.5rem;
            }

            .links-section {
                padding: 2rem 1.5rem;
            }

            .links-section ul {
                column-count: 1;
            }

            article h2 {
                font-size: 1.5rem;
            }

            article h3 {
                font-size: 1.25rem;
            }
        }

        @media (max-width: 480px) {
            h1 {
                font-size: 1.5rem;
            }

            article p,
            .transition-section p,
            .links-section ul li a {
                font-size: 1rem;
            }
        }