i want to add a blue color to the display, where i can enter the code [closed]

@override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text(widget.title)),
      body: Center(
        child: _widgetOptions[_selectedIndex],
      ),
      drawer: Drawer(
        // Add a ListView to the drawer. This ensures the user can scroll
        // through the options in the drawer if there isn't enough vertical
        // space to fit everything.
        child: ListView(
          // Important: Remove any padding from the ListView.
          padding: EdgeInsets.zero,
          children: [
            const DrawerHeader(
              decoration: BoxDecoration(
                color: Colors.,
              ),
              child: Text('Drawer Header'),
            ),
            ListTile(
              title: const Text('Home'),
              selected: _selectedIndex == 0,
              onTap: () {
                // Update the state of the app
                _onItemTapped(0);
                // Then close the drawer
                Navigator.pop(context);
              },
            ),

i want to add a blue color to the display, where i can enter the code