* { 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;
        }
        .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; }
        }