Change Color In Specific Columns

I have a macro that changes the color on a row, but depending on which cell I am in different columns arwe changing color. What I want is that if I make a change in row 1 want the color in A1:L1 to change and if i change row 2 i want A2:L2 to change, so alwaws the columns A to L in respective row. My macro

Sub Markera_Ny()
Dim intRadnr As Integer
Dim intStartrad As Integer
Dim intSlutrad As Integer
Dim Box As Integer
Dim Rad As Integer
intRadnr = ActiveCell.Row
intStartrad = ActiveSheet.Range("First").Row
intSlutrad = ActiveSheet.Range("Last").Row
If intRadnr < intStartrad Or intRadnr >= intSlutrad Then
MsgBox "Macro can only be executed in rows 21 to 1000"
Exit Sub
End If....................