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

        body {
            font-family: 'Helvetica Neue', Arial, Helvetica, sans-serif;
            line-height: 1.6;
            color: #333;
            background-color: #f5f5f5;
        }

        .header {
            background-color: #fff;
            border-bottom: 2px solid #e0e0e0;
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
        }

        .hdr-top {
            max-width: 1200px;
            margin: 0 auto;
            padding: 15px 20px;
        }

        .hdr-top-in {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .hdr-logo {
            font-size: 24px;
            font-weight: 700;
            color: #2c3e50;
        }

        .hdr-menu {
            list-style: none;
            display: flex;
            gap: 20px;
        }

        .help-btn {
            color: #0066cc;
            text-decoration: none;
            font-weight: 500;
            cursor: pointer;
            padding: 8px 16px;
            border-radius: 4px;
            transition: background-color 0.3s;
        }

        .help-btn:hover {
            background-color: #f0f0f0;
        }

        .show-mob {
            display: none;
        }

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 20px;
        }

        .content {
            background-color: #fff;
            border-radius: 8px;
            padding: 40px;
            margin-bottom: 30px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.08);
        }

        h1 {
            font-size: 2.5em;
            color: #2c3e50;
            margin-bottom: 30px;
            padding-bottom: 20px;
            border-bottom: 3px solid #3498db;
        }

        article {
            margin-bottom: 40px;
        }

        article p {
            margin-bottom: 20px;
            font-size: 1.1em;
            line-height: 1.8;
            color: #555;
        }

        article h2 {
            font-size: 1.8em;
            color: #2c3e50;
            margin-top: 30px;
            margin-bottom: 15px;
        }

        article h3 {
            font-size: 1.4em;
            color: #34495e;
            margin-top: 25px;
            margin-bottom: 12px;
        }

        article h4 {
            font-size: 1.2em;
            color: #34495e;
            margin-top: 20px;
            margin-bottom: 10px;
        }

        .transition-section {
            background-color: #f8f9fa;
            border-radius: 8px;
            padding: 30px;
            margin-bottom: 30px;
        }

        .transition-section p {
            font-size: 1.05em;
            line-height: 1.7;
            color: #555;
            margin-bottom: 15px;
        }

        .links-section {
            background-color: #fff;
            border-radius: 8px;
            padding: 40px;
            box-shadow: 0 2px 8px rgba(0,0,0,0.08);
        }

        .links-section h3 {
            font-size: 1.5em;
            color: #2c3e50;
            margin-top: 30px;
            margin-bottom: 20px;
            padding-bottom: 10px;
            border-bottom: 2px solid #e0e0e0;
        }

        .links-section h3:first-child {
            margin-top: 0;
        }

        .links-section ul {
            list-style: none;
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 12px 30px;
            margin-bottom: 30px;
        }

        .links-section li {
            position: relative;
            padding-left: 20px;
        }

        .links-section li:before {
            content: "→";
            position: absolute;
            left: 0;
            color: #3498db;
            font-weight: bold;
        }

        .links-section a {
            color: #0066cc;
            text-decoration: none;
            transition: color 0.3s;
            font-size: 1em;
        }

        .links-section a:hover {
            color: #004499;
            text-decoration: underline;
        }

        @media (max-width: 768px) {
            .hide-mob {
                display: none;
            }

            .show-mob {
                display: block;
                font-size: 24px;
                cursor: pointer;
            }

            .container {
                padding: 10px;
            }

            .content {
                padding: 20px;
            }

            h1 {
                font-size: 1.8em;
            }

            article p {
                font-size: 1em;
            }

            article h2 {
                font-size: 1.5em;
            }

            article h3 {
                font-size: 1.3em;
            }

            .links-section {
                padding: 20px;
            }

            .links-section ul {
                grid-template-columns: 1fr;
                gap: 10px;
            }

            .transition-section {
                padding: 20px;
            }
        }

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

            .hdr-logo {
                font-size: 20px;
            }

            .hdr-top {
                padding: 10px 15px;
            }
        }