Code chỉ tô màu đến dòng thứ 12 (1 người xem)

[Excel365]

Cho em em hỏi sao code chỉ tô màu đến dòng thứ 12, Nếu muôn tô màu cho hơn 12 dòng thì chỉnh như thế nào các anh, chị.
Code sưu tầm trên http://tinhocvp.blogspot.com/2014/02/anh-dau-cac-gia-tri-trung-nhau-bang.html

Sub Highlight_Duplicate()
    Dim ws As Worksheet
    Dim cell As Range
    Dim myrng As Range
    Dim clr As Long
    Dim lastcell As Range
    Dim i As Long
    Dim lastrow As Long

    Set ws = ThisWorkbook.ActiveSheet

    'Vung can danh dau gia tri trung nhau
    Set myrng = ws.Range("C4:F" & Range("C" & ws.Rows.Count).End(xlUp).Row)

    With myrng
        Set lastcell = .Cells(.Cells.Count)
    End With

    myrng.Interior.ColorIndex = xlNone
    clr = 3

    For Each cell In myrng
        'Kiem tra so gia tri trung nhau trong vung, neu co hai gia tri trung nhau tro len thi thuc hien
        If Application.WorksheetFunction.CountIf(myrng, cell) > 1 Then
            'Neu la o dau tien cua cac gia tri trung nhau trong vung
            If myrng.Find(what:=cell, lookat:=xlWhole, MatchCase:=False, after:=lastcell).Address = cell.Address Then
                'Thiet lap mau
                cell.Interior.ColorIndex = clr
                clr = clr + 1
                i = i + 1
            Else
                'Thiet lap mau tu o thu 2 voi cac gia tri trung nhau
                cell.Interior.ColorIndex = myrng.Find(what:=cell, lookat:=xlWhole, MatchCase:=False, after:=lastcell).Interior.ColorIndex
            End If
        End If
    Next

     'Lay dong cuoi cung cua vung du lieu
    lastrow = Cells(Rows.Count, "A").End(xlUp).Row
    Range("A" & lastrow + 2).Value = "Tong so co " & i & " gia tri trung nhau"
End Sub

Read more: http://tinhocvp.blogspot.com/2014/02/anh-dau-cac-gia-tri-trung-nhau-bang.html#ixzz399HhuW3U