Date Stamp On Worksheet Change

Hi all,

I have the following little piece of code that adds the date to C3 whenever the workbook is saved:

Private Sub Workbook_BeforeSave(ByVal SaveAsUI As Boolean, Cancel As Boolean)
   
   Sheets("Resourcing").Range("C3").Value = Now()
   
End Sub

Can anyone advise on how (if it is at all possible) to only run this code when someone changes a cell value (in particular the cells in range A7:AY186 and A189:AY216)?

TIA,

SamuelT