want to initialize TimeZone package in flutter ,code give this errors

Errors

Performing hot reload...
Syncing files to device sdk gphone x86 arm...
lib/pages/clock.dart:12:8: Error: Not found: 'dart:html'
import 'dart:html';
       ^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/timezone-0.8.0/lib/browser.dart:16:8: Error: Not found: 'dart:html'
import 'dart:html';
       ^
/C:/src/flutter/.pub-cache/hosted/pub.dartlang.org/timezone-0.8.0/lib/browser.dart:47:10: Error: Getter not found: 'HttpRequest'.
  return HttpRequest.request(path,

         ^^^^^^^^^^^

Widget

    import 'package:flutter/cupertino.dart';
    import 'package:flutter/material.dart';
    import 'package:clock/clock.dart';
    import 'package:timezone/standalone.dart';
    import 'package:timezone/timezone.dart';
    import 'package:intl/date_symbol_data_local.dart';
    import 'package:intl/intl.dart';
    import 'package:timezone/data/latest_all.dart';
    import 'package:time/services/time.dart';
    import 'package:timezone/data/latest.dart' as tz;
    import 'package:timezone/browser.dart' as ts;
    
    class Clock extends StatefulWidget {
      const Clock({Key? key}) : super(key: key);
    
      @override
      _ClockState createState() => _ClockState();
    }
    
    class _ClockState extends State<Clock> {
      var location;
      @override
      void initState() {
        //Time now = new Time();
        // TODO: implement initState
        super.initState();
        // now = new Time();
      }
    
      @override
      Widget build(BuildContext context) {
        return Scaffold(
          appBar: AppBar(),
          body: Container(
            child: Column(children: [
              ElevatedButton(
                  onPressed: () {
                    // tz.initializeTimeZones();
                    ts.initializeTimeZone();
                    ts.initializeTimeZone('packages/timezone/data/latest_all.tzf');
                    var detroit = ts.getLocation('America/Detroit');
                    print(detroit);
                    var now = ts.TZDateTime.now(detroit);
                  },
                  child: Text("press me")),
              SizedBox(
                height: 20,
              ),
              SizedBox(
                height: 40,
              ),
              Text('$location'),
              ElevatedButton(
                  onPressed: () {
                    DateTime now = new DateTime.now();
                    var formatter = new DateFormat.Hm();
                    String nowFormatted = formatter.format(now);
                    print(now.timeZoneOffset);
                    print(nowFormatted);
                  },
                  child: Text("pres me")),
              SizedBox(
                height: 20,
              ),
              Text('${DateTime.now()}')
            ]),
          ),
        );
      }
    }