Some relative stuff

lib/pages/order_pay.dart

@@ -0,0 +1,26 @@
+import 'dart:ui_web' as ui;
+
+import 'package:flutter/material.dart';
+import 'package:universal_html/html.dart';
+
+class OrderPayPage extends StatelessWidget {
+  const OrderPayPage({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    registerHtmlElementView();
+    return const HtmlElementView(
+      viewType: 'payment-html',
+    );
+  }
+
+  void registerHtmlElementView() {
+    ui.platformViewRegistry.registerViewFactory(
+        'payment-html',
+        (int viewId) => IFrameElement()
+          ..src = 'payment.html'
+          ..style.width = '100%'
+          ..style.height = '500px'
+          ..style.border = 'none');
+  }
+}