Option Explicit
Private Sub Worksheet_BeforeDoubleClick(ByVal Target As Range, Cancel As Boolean)
If Not Application.Intersect(Target, Range("A1:BW40")) Is Nothing Then
With Target.Interior
.ColorIndex = IIf(.ColorIndex = 1, 3, IIf(.ColorIndex = 3, xlNone, 1))
End With
Cancel = True
End If
End Sub