Please help modify this code FOR hide rows in sheet1?

I have this code to hide the empty rows in a specific range, and it works well, but it hides all the rows in all the sheets in the Excel file.
It needs to be modified to work on Sheet1 only.

  Sub HIDDEN()
    Dim xRg As Range
    Application.ScreenUpdating = False
         For Each xRg In Range("C18:C53")
            If xRg.Value < 1 Then
                xRg.EntireRow.HIDDEN = True
        
            Else
                xRg.EntireRow.HIDDEN = False
            End If
        Next xRg
    Application.ScreenUpdating = True


  End Sub