ninja10 Padding

// Using margin in padding

      body: Container(
        padding : EdgeInsets.fromLTRB(10.0, 20.0, 30.0, 40.0),
        margin : EdgeInsets.all(30.0),
        color : Colors.grey,
        child : Text('Hello World'),
      ),
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// Using a padding widget

      body: Padding(
        padding: EdgeInsets.all(30.0),
        child: Text('Hello'),
      ),

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// FULL CODE

import 'package:flutter/material.dart';

void main() => runApp(MaterialApp(
      home: Home(),
    ));

class Home extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(
          'App bar',
          style: TextStyle(color: Colors.white),
        ),
        centerTitle: true,
        backgroundColor: Colors.red,
      ),
      body: Padding(
        padding: EdgeInsets.all(30.0),
        child: Text('Hello'),
      ),
      floatingActionButton: FloatingActionButton(
        child: Text('click me'),
        onPressed: null,
        backgroundColor: Colors.red,
      ),
    );
  }
}