import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      theme: ThemeData(
        inputDecorationTheme: const InputDecorationThemeData(
          activeIndicatorBorder: BorderSide(color: Colors.purpleAccent, width: 4.0),
        ),
      ),
      home: const Scaffold(
        body: Padding(
          padding: EdgeInsets.all(8.0),
          child: SizedBox(
            width: 200.0,
            child: TextField(decoration: InputDecoration(labelText: 'Flutter !!!', filled: true)),
          ),
        ),
      ),
    );
  }
}