:root {
            --primary: #6c5ce7;
            --primary-dark: #5649c0;
            --secondary: #fd79a8;
            --success: #00b894;
            --dark: #2d3436;
            --light: #f7f7f7;
            --gray: #dfe6e9;
            --card-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
            --transition: all 0.4s ease;
        }

        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }

        body {
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
            color: var(--dark);
            min-height: 100vh;
            padding: 20px;
            margin-top: 45px;
        }

        .container {
            max-width: 1400px;
            margin: 0 auto;
        }

        .page-title {
            text-align: center;
            margin: 20px 0 30px;
            font-size: 2.5rem;
            font-weight: 800;
            background: linear-gradient(45deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            background-clip: text;
            color: transparent;
            text-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
        }

        .subtitle {
            text-align: center;
            color: #636e72;
            margin-bottom: 40px;
            font-size: 1.2rem;
        }

        .filter-bar {
            display: flex;
            justify-content: center;
            gap: 12px;
            margin-bottom: 40px;
            flex-wrap: wrap;
        }

        .filter-btn {
            padding: 10px 20px;
            border: none;
            background: white;
            border-radius: 50px;
            font-weight: 600;
            cursor: pointer;
            transition: var(--transition);
            box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .filter-btn:hover, .filter-btn.active {
            background: var(--primary);
            color: white;
            transform: translateY(-3px);
        }

        .store-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 30px;
            margin-bottom: 60px;
        }

        /* Flip Card Styles */
        .flip-card {
            background-color: transparent;
            width: 100%;
            height: 380px;
            perspective: 1000px;
        }

        .flip-card-inner {
            position: relative;
            width: 100%;
            height: 100%;
            text-align: center;
            transition: transform 0.8s;
            transform-style: preserve-3d;
        }

        .flip-card:hover .flip-card-inner {
            transform: rotateY(180deg);
        }

        .flip-card-front, .flip-card-back {
            position: absolute;
            width: 100%;
            height: 100%;
            -webkit-backface-visibility: hidden;
            backface-visibility: hidden;
            border-radius: 20px;
            box-shadow: var(--card-shadow);
            overflow: hidden;
        }

        .flip-card-front {
            background-color: white;
            color: var(--dark);
            display: flex;
            flex-direction: column;
        }

        .flip-card-back {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            color: white;
            transform: rotateY(180deg);
            display: flex;
            flex-direction: column;
            justify-content: center;
            padding: 25px;
        }

        .product-thumbnail {
            height: 180px;
            width: 100%;
            display: flex;
            align-items: center;
            justify-content: center;
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
            position: relative;
            overflow: hidden;
        }

        .product-thumbnail img {
            max-width: 100%;
            max-height: 100%;
            object-fit: contain;
            border-radius: 5px;
        }

        .product-info {
            padding: 20px;
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }

        .product-title {
            font-size: 1.3rem;
            font-weight: 700;
            margin-bottom: 10px;
            color: var(--dark);
        }

        .product-description {
            color: #636e72;
            font-size: 0.9rem;
            margin-bottom: 15px;
            line-height: 1.5;
            flex-grow: 1;
        }

        .product-meta {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .product-type {
            background: var(--gray);
            padding: 5px 12px;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 600;
        }

        .price-container {
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .original-price {
            text-decoration: line-through;
            color: #636e72;
            font-size: 0.9rem;
        }

        .free-price {
            font-weight: 800;
            font-size: 1.2rem;
            color: var(--success);
        }

        .explore-btn {
            width: 100%;
            padding: 12px;
            background: var(--primary);
            color: white;
            border: none;
            border-radius: 12px;
            font-weight: 700;
            cursor: pointer;
            transition: var(--transition);
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            margin-top: 15px;
            text-decoration: none;
        }

        .explore-btn:hover {
            background: var(--primary-dark);
            transform: translateY(-3px);
        }

        .back-title {
            font-size: 1.5rem;
            font-weight: 700;
            margin-bottom: 15px;
        }

        .back-description {
            margin-bottom: 20px;
            line-height: 1.6;
        }

        .features-list {
            text-align: left;
            margin-bottom: 20px;
            padding-left: 20px;
        }

        .features-list li {
            margin-bottom: 8px;
        }

        .view-details-btn {
            width: 100%;
            padding: 12px;
            background: white;
            color: var(--primary);
            border: none;
            border-radius: 12px;
            font-weight: 700;
            cursor: pointer;
            transition: var(--transition);
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
            text-decoration: none;
        }

        .view-details-btn:hover {
            background: var(--light);
            transform: translateY(-3px);
        }

        /* Popular Badge */
        .popular-badge {
            position: absolute;
            top: 15px;
            right: 15px;
            background: var(--success);
            color: white;
            padding: 5px 10px;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 700;
            z-index: 2;
        }

        /* Responsive Design */
        @media (max-width: 1200px) {
            .store-grid {
                grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            }
        }

        @media (max-width: 768px) {
            .store-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 20px;
            }
            
            .page-title {
                font-size: 2rem;
            }
            
            .filter-bar {
                gap: 8px;
            }
            
            .filter-btn {
                padding: 8px 16px;
                font-size: 0.9rem;
            }
        }

        @media (max-width: 576px) {
            .store-grid {
                grid-template-columns: 1fr;
            }
            
            .page-title {
                font-size: 1.8rem;
            }
            
            .flip-card {
                height: 350px;
            }
            
            .product-thumbnail {
                height: 150px;
            }
        }

        /* Animation for cards */
        @keyframes fadeIn {
            from { opacity: 0; transform: translateY(20px); }
            to { opacity: 1; transform: translateY(0); }
        }

        .flip-card {
            animation: fadeIn 0.5s ease forwards;
        }

        .flip-card:nth-child(2) { animation-delay: 0.1s; }
        .flip-card:nth-child(3) { animation-delay: 0.2s; }
        .flip-card:nth-child(4) { animation-delay: 0.3s; }
        .flip-card:nth-child(5) { animation-delay: 0.4s; }
        .flip-card:nth-child(6) { animation-delay: 0.5s; }
        .flip-card:nth-child(7) { animation-delay: 0.6s; }
        .flip-card:nth-child(8) { animation-delay: 0.7s;