/* --- CSS Variables --- */
        :root {
            --primary-blue: #004481;
            --accent-cyan: #00AEEF;
            --warm-orange: #FF6720;
            --text-dark: #333333;
            --text-light: #FFFFFF;
            --bg-light: #F4F7F9;
            --card-bg: #FFFFFF;
        }

        html {
            scroll-behavior: smooth;
        }

        /* --- Reset & Base Styles --- */
        * { box-sizing: border-box; margin: 0; padding: 0; }
        body { font-family: 'Prompt', sans-serif; color: var(--text-dark); background-color: var(--bg-light); line-height: 1.6; }
        a { text-decoration: none; transition: 0.3s; }
        ul { list-style: none; }
        img { max-width: 100%; height: auto; display: block; }

        .container { max-width: 1000px; margin: 0 auto; padding: 0 20px; }

        /* --- Header (Logo & Booking Action) --- */
        header { 
            display: flex; justify-content: space-between; align-items: center; 
            padding: 15px 20px; background-color: rgba(255,255,255,0.95); 
            position: sticky; top: 0; z-index: 100; box-shadow: 0 2px 10px rgba(0,0,0,0.05);
        }
        .logo { font-size: 1.5rem; font-weight: 700; color: var(--primary-blue); }
        .logo span { color: var(--accent-cyan); }
        .btn-reserve-top { 
            background-color: var(--warm-orange); color: var(--text-light); 
            padding: 8px 20px; border-radius: 50px; font-weight: 600; font-size: 0.9rem; 
            cursor: pointer;
        }

        /* --- Utility Classes --- */
        .btn { display: inline-block; padding: 15px 30px; border-radius: 50px; font-weight: 600; text-align: center; border: none; cursor: pointer; transition: 0.3s; font-family: 'Prompt', sans-serif; }
        .btn-primary { background-color: var(--warm-orange); color: var(--text-light); font-size: 1.1rem; box-shadow: 0 4px 15px rgba(255, 103, 32, 0.3); }
        .btn-primary:hover { background-color: #e55a15; transform: translateY(-2px); box-shadow: 0 6px 20px rgba(255, 103, 32, 0.4); color: var(--text-light); }
        .section-title { font-size: 2.2rem; text-align: center; margin-bottom: 0.5rem; color: var(--primary-blue); font-weight: 700; }
        .section-subtitle { font-size: 1.1rem; text-align: center; margin-bottom: 2.5rem; color: #666; font-weight: 300; }

        /* --- Section 1: Hero --- */
        .hero { 
            background: linear-gradient(rgba(0, 68, 129, 0.8), rgba(0, 0, 0, 0.5)), 
                        url('https://images.unsplash.com/photo-1516528387618-afa90b13e000?q=80&w=2000&auto=format&fit=crop') no-repeat center center/cover;
            color: var(--text-light); padding: 100px 0; text-align: center;
        }
        .hero-content h1 { font-size: 3rem; font-weight: 700; line-height: 1.2; margin-bottom: 1.5rem; }
        .hero-content p { font-size: 1.2rem; margin-bottom: 2.5rem; font-weight: 300; max-width: 700px; margin-left: auto; margin-right: auto; }

        /* --- Section 2: Problem --- */
        .problem { padding: 60px 0; background-color: var(--text-light); }
        .problem-list { display: flex; flex-direction: column; gap: 15px; max-width: 500px; margin: 0 auto; }
        .problem-item { 
            background: var(--bg-light); padding: 15px 25px; border-radius: 10px; 
            border-left: 5px solid var(--accent-cyan); font-weight: 600; font-size: 1.1rem; 
            color: var(--primary-blue); display: flex; align-items: center; gap: 15px;
        }

        /* --- Section 3: Solution (All 3 Formulas Picture) --- */
        .solution { padding: 60px 0; background-color: var(--bg-light); text-align: center; }
        .product-group-mockup { 
            margin: 20px auto; max-width: 700px; border-radius: 15px; overflow: hidden;
            box-shadow: 0 10px 30px rgba(0,0,0,0.1); border: 2px dashed #ccc;
        }
        .product-group-mockup img { width: 100%; display: block; }

        /* --- Section 4: 2-in-1 How it works (Zigzag) --- */
        .how-it-works { padding: 60px 0; background-color: var(--text-light); }
        .zigzag-row { display: flex; align-items: center; gap: 30px; margin-bottom: 40px; }
        .zigzag-row.reverse { flex-direction: row-reverse; }
        .img-box { 
            flex: 1; height: 200px; background: var(--bg-light); border-radius: 15px; 
            display: flex; align-items: center; justify-content: center; 
            color: #888; border: 2px dashed #ccc; overflow: hidden;
        }
        .img-box img { width: 100%; height: 100%; object-fit: cover; }
        .text-box { flex: 1; }
        .text-box h3 { font-size: 1.4rem; color: var(--primary-blue); margin-bottom: 10px; }
        .text-box p { color: #555; }

        /* --- Section 5: 3 Formulas (Swipeable Cards) --- */
        .formulas { padding: 60px 0; background-color: var(--bg-light); overflow: hidden; }
        .swipe-hint { text-align: center; font-size: 0.9rem; color: #888; margin-bottom: 20px; }
        .carousel { 
            display: flex; gap: 20px; overflow-x: auto; padding-bottom: 20px; 
            scroll-snap-type: x mandatory; scrollbar-width: none; 
        }
        .carousel::-webkit-scrollbar { display: none; }
        .card { 
            min-width: 280px; background: var(--card-bg); border-radius: 15px; padding: 25px; 
            scroll-snap-align: center; text-align: center; box-shadow: 0 5px 15px rgba(0,0,0,0.05); 
        }
        .card-img { 
            height: 180px; background: var(--bg-light); border-radius: 10px; margin-bottom: 20px; 
            display: flex; align-items: center; justify-content: center; color: #aaa; border: 1px dashed #ccc;
        }
        .card-img img { height: 100%; object-fit: cover; border-radius: 10px;}
        .card h3 { font-size: 1.3rem; margin-bottom: 5px; }
        .card-blue h3 { color: #0056b3; }
        .card-green h3 { color: #28a745; }
        .card-yellow h3 { color: #d39e00; }
        .card p.scent { font-weight: 600; font-size: 0.95rem; color: #444; margin-bottom: 10px; }
        .card p.desc { font-size: 0.9rem; color: #666; }

        /* --- Section 6: Pre-order Form --- */
        .preorder { padding: 80px 0; background: linear-gradient(135deg, var(--primary-blue), #002244); color: var(--text-light); }
        .preorder .section-title { color: var(--text-light); }
        .preorder .section-subtitle { color: rgba(255,255,255,0.8); }
        .form-container { background: white; padding: 40px; border-radius: 15px; box-shadow: 0 20px 40px rgba(0,0,0,0.3); max-width: 700px; margin: 0 auto; color: var(--text-dark); }
        .form-group { margin-bottom: 20px; text-align: left; }
        .form-group label { display: block; margin-bottom: 8px; font-weight: 600; color: var(--primary-blue); font-size: 1rem; }
        .form-group input, .form-group select, .form-group textarea { width: 100%; padding: 12px; border: 1.5px solid #ccc; border-radius: 8px; font-family: 'Prompt', sans-serif; font-size: 1rem; background-color: #fafafa; }
        .form-group input:focus, .form-group select:focus, .form-group textarea:focus { border-color: var(--accent-cyan); outline: none; }
        .submit-btn { width: 100%; font-size: 1.2rem; padding: 15px; margin-top: 10px; }

        /* --- Footer --- */
        footer { padding: 30px 0; background-color: #001529; color: rgba(255,255,255,0.5); text-align: center; font-size: 0.9rem; }

        /* --- Responsive Styles --- */
        @media (max-width: 768px) {
            .hero-content h1 { font-size: 2.2rem; }
            .section-title { font-size: 1.8rem; }
            .zigzag-row, .zigzag-row.reverse { flex-direction: column; text-align: center; gap: 15px; }
            .img-box { width: 100%; }
        }
        @media (min-width: 900px) {
            .carousel { justify-content: center; }
        }