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

        body {
            background: #f3f4f6;
            font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
            line-height: 1.5;
            padding: 24px 16px;
            color: #1e293b;
        }

        .checkout-wrapper {
            max-width: 1280px;
            margin: 0 auto;
        }

        .checkout-grid {
            display: grid;
            grid-template-columns: 1fr 1.2fr;
            gap: 28px;
        }

        .card {
            background: #ffffff;
            border-radius: 28px;
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.03), 0 2px 6px rgba(0, 0, 0, 0.05);
            overflow: hidden;
            border: 1px solid #eef2f6;
        }

        .card-header {
            padding: 1.5rem 1.75rem 0.75rem 1.75rem;
            border-bottom: 1px solid #edf2f7;
        }

        .card-header h2 {
            font-size: 1.35rem;
            font-weight: 600;
            letter-spacing: -0.2px;
            color: #0f172a;
        }

        .card-content {
            padding: 1.5rem 1.75rem 1.75rem 1.75rem;
        }

        .form-group {
            margin-bottom: 1.2rem;
        }

        .form-group label {
            display: block;
            font-size: 0.85rem;
            font-weight: 500;
            margin-bottom: 6px;
            color: #334155;
        }

        .form-control {
            width: 100%;
            padding: 12px 14px;
            background-color: #f9fafb;
            border: 1px solid #e2e8f0;
            border-radius: 16px;
            font-size: 0.9rem;
            transition: 0.15s;
            font-family: inherit;
        }

        .form-control:focus {
            outline: none;
            border-color: #94a3b8;
            background-color: #ffffff;
            box-shadow: 0 0 0 3px rgba(148, 163, 184, 0.1);
        }

        .radio-group {
            display: flex;
            gap: 20px;
            margin-top: 8px;
            flex-wrap: wrap;
        }
        .radio-option {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 0.9rem;
        }
        .radio-option input {
            accent-color: #2563eb;
            width: 18px;
            height: 18px;
            margin: 0;
        }

        .order-item {
            display: flex;
            gap: 14px;
            margin-bottom: 24px;
            padding-bottom: 20px;
            border-bottom: 1px solid #f0f2f5;
        }
        .item-image {
            width: 90px;
            height: 90px;
            background: #f8fafc;
            border-radius: 18px;
            display: flex;
            align-items: center;
            justify-content: center;
            overflow: hidden;
            flex-shrink: 0;
        }
        .item-image img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }
        .item-details {
            flex: 1;
        }
        .item-title {
            font-weight: 700;
            font-size: 1rem;
            margin-bottom: 6px;
            color: #0f172a;
            line-height: 1.4;
        }
        .item-price {
            font-weight: 500;
            color: #2d3a5e;
            font-size: 1rem;
            margin-top: 4px;
        }
        .item-sku {
            font-size: 0.7rem;
            color: #6c757d;
            margin-top: 6px;
        }

        .quantity-section {
            display: flex;
            align-items: center;
            justify-content: space-between;
            margin-top: 14px;
            flex-wrap: wrap;
            gap: 12px;
        }
        .quantity-label {
            font-size: 0.85rem;
            font-weight: 600;
            color: #334155;
        }
        .quantity-selector {
            display: inline-flex;
            align-items: center;
            background: #f8fafc;
            border-radius: 60px;
            border: 1px solid #e2edf7;
            overflow: hidden;
        }
        .qty-btn {
            background: white;
            border: none;
            font-size: 1.25rem;
            font-weight: 500;
            width: 38px;
            height: 38px;
            cursor: pointer;
            transition: 0.1s;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            color: #1f3a6b;
            background: #ffffff;
        }
        .qty-btn:active {
            background: #eef2ff;
        }
        .qty-value {
            width: 48px;
            text-align: center;
            font-weight: 600;
            font-size: 1rem;
            background: white;
            border: none;
            border-left: 1px solid #e2edf7;
            border-right: 1px solid #e2edf7;
            padding: 8px 0;
        }
        .item-total {
            font-weight: 700;
            font-size: 1rem;
            color: #0f172a;
            background: #f8fafc;
            padding: 6px 14px;
            border-radius: 40px;
        }

        .price-summary {
            margin-top: 20px;
            background: #fafcff;
            border-radius: 24px;
            padding: 6px 0;
        }
        .summary-row {
            display: flex;
            justify-content: space-between;
            padding: 12px 0;
            font-size: 0.95rem;
            border-bottom: 1px dashed #eef2f8;
        }
        .summary-row.total-row {
            border-bottom: none;
            font-weight: 800;
            font-size: 1.25rem;
            margin-top: 8px;
            padding-top: 16px;
            border-top: 2px solid #e9edf2;
            color: #0f172a;
        }

        .payment-buttons {
            margin-top: 30px;
            display: flex;
            flex-direction: column;
            gap: 14px;
        }
        .pay-btn {
            width: 100%;
            padding: 14px 12px;
            border-radius: 60px;
            font-weight: 700;
            font-size: 1rem;
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 12px;
            border: none;
            cursor: not-allowed;
            opacity: 1;
            background: #eef2ff;
            color: #1e293b;
            pointer-events: none;
        }
        .pay-credit {
            background: #1e293b;
            color: white;
        }
        .pay-paypal {
            background: #ffc439;
            color: #1f2a3e;
        }
        .pay-credit svg, .pay-paypal svg {
            width: 22px;
            height: 22px;
        }
        .secure-note {
            display: flex;
            align-items: center;
            justify-content: center;
            gap: 12px;
            margin-top: 20px;
            font-size: 0.7rem;
            color: #5b6e8c;
            background: #f9fafb;
            border-radius: 60px;
            padding: 10px 14px;
        }

        @media (max-width: 800px) {
            .checkout-grid {
                grid-template-columns: 1fr;
                gap: 20px;
            }
            .quantity-section {
                flex-direction: column;
                align-items: flex-start;
            }
            .item-total {
                align-self: flex-end;
            }
        }