Want to create WPF in MVVM pattern

The MainWindow xaml has an named outer grid View.

The xaml code behind (MainWindow.xaml.cs) may only contain a constructor

which sets the View.DataContext to an instance of a new ViewModel class.

 public partial class MainWindow : Window

{ 

public MainWindow() 

{ 

InitializeComponent(); 

View.DataContext = new ViewModel();

 } 

}

Use xaml and additional code / classes to implement the bindings to implement
the following behavior.
MainWindow user interface contains :
two input textboxes A and B (with Width=100 and Height=25).
two result textboxes containing : C = A + B, and D = A * B, these update, when A or B change.
MainWindow background color is:
LightBlue when mouse cursor enters A inputbox
LightGreen when mouse cursor enters B inputbox
LightGray all other cases.