MaterialApp(
  home: Scaffold(
    appBar: AppBar(title: Text('My First App')),
    body: Center(child: Text('Hello, Flutter!')),
    floatingActionButton: FloatingActionButton(
      onPressed: () {},
      child: Icon(Icons.add),
    ),
  ),
)

flutter:
  assets:
    - images/logo.png

Container(
  margin: EdgeInsets.all(20),
  padding: EdgeInsets.all(16),
  child: Text('I have margin and padding!'),
)

Row(
  children: [
    Icon(Icons.star, color: Colors.amber),
    Icon(Icons.star, color: Colors.amber),
    Icon(Icons.star_border, color: Colors.amber),
  ],
)