:root {
            --solid-color: #ff7675;
            --liquid-color: #74b9ff;
            --bg-color: #f1f2f6;
        }

        body {
            font-family: 'Itim', cursive;
            background-color: var(--bg-color);
            margin: 0;
            padding: 20px;
            text-align: center;
            color: #2f3542;
        }

        /* --- ปุ่มกลับหน้าหลัก (สไตล์เดียวกันทุกหน้า) --- */
        .home-button {
            position: fixed;
            top: 20px;
            left: 20px;
            background: #ffeaa7;
            color: #d63031;
            padding: 10px 15px;
            border-radius: 15px;
            box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
            text-decoration: none;
            display: flex;
            align-items: center;
            transition: transform 0.2s, background 0.2s;
            z-index: 100;
        }

        .home-button:hover {
            transform: scale(1.05);
            background: #ffe38f;
        }

        .home-button .icon-home {
            font-size: 2rem;
            margin-right: 8px;
        }

        .home-button .text-home {
            font-weight: bold;
            font-size: 1.1rem;
        }

        .container {
            max-width: 800px;
            margin: 60px auto 0;
        }

        .header-title {
            font-size: 2.5rem;
            color: #d35400;
            margin-bottom: 10px;
        }

        /* การ์ดเปรียบเทียบ */
        .comparison-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 20px;
            margin-top: 30px;
        }

        .card {
            background: white;
            border-radius: 30px;
            padding: 25px;
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
            border: 5px solid transparent;
        }

        .solid-card {
            border-color: var(--solid-color);
        }

        .liquid-card {
            border-color: var(--liquid-color);
        }

        .icon-large {
            font-size: 5rem;
            margin-bottom: 15px;
        }

        h2 {
            font-size: 2rem;
            margin: 10px 0;
        }

        .solid-card h2 {
            color: var(--solid-color);
        }

        .liquid-card h2 {
            color: var(--liquid-color);
        }

        .fact-list {
            text-align: left;
            font-size: 1.3rem;
            line-height: 1.6;
        }

        .fact-list li {
            list-style: none;
            margin-bottom: 10px;
        }

        /* มินิเกมทดสอบ */
        .game-area {
            margin-top: 40px;
            background: #ffffff;
            padding: 30px;
            border-radius: 30px;
            box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
        }

        .btn-check {
            background: #2ecc71;
            color: white;
            border: none;
            padding: 10px 30px;
            font-size: 1.5rem;
            border-radius: 50px;
            cursor: pointer;
            font-family: 'Itim';
            margin: 10px;
        }

        .result-msg {
            font-size: 1.5rem;
            height: 40px;
            margin-top: 20px;
            font-weight: bold;
        }

        @media (max-width: 600px) {
            .text-home {
                display: none;
            }
        }