Macro To Count Rows With Coloured Cells

I have a sheet with colour coded cells and I need a macro that counts the number of rows with coloured cells.

I've tried the following code but I always get a count of 0 which isn't right.


Sub Count_Coloured_Cells()

Sheets("Issues").Select
Dim i, c
Dim LastRow As Long
i = 1
c = 0
LastRow = Range("A65536").End(xlUp).Row

Do While i < LastRow + 1
If Rows(1 + i & ":" & 1 + i).Interior.ColorIndex xlNone Then
c = c + 1
End If
i = i + 1
Loop

MsgBox (c)

End Sub

Remember, it's the number of rows I need to count (i.e. one row may have several colour coded cells but I only need to count it once).