Sub O1_Import()
    Dim filePath As String
    Dim lines As Variant
    Dim i As Long
    Dim writeRow As Long

    Set ws = Me
    
    On Error GoTo ErrorHandler
    
    ' Step 1: Select CSV file
    filePath = SelectCSVFile()
    If filePath = "" Then Exit Sub
    
    ' Step 2: Read CSV and return 2D array
    lines = ReadCSVAs2DArrayStrict(filePath, 4, "shift-jis", True)
    
    ' Step 3: Clear data rows
    Call ClearDataRows(ws, 7, 3)
    
    ' Step 4: Import data
    writeRow = 7
    For i = LBound(lines, 1) To UBound(lines, 1)
        If Not isRowEmpty Then
            Dim colOffset As Long
            For colOffset = 1 To 4
                ws.Cells(writeRow, 2 + colOffset).Value = CleanCSVField(CStr(lines(i, colOffset)))
            Next colOffset
            writeRow = writeRow + 1
        End If
    Next i
    
    MsgBox writeRow - 7 & " rows imported.", vbInformation
    
    Exit Sub

ErrorHandler:
    MsgBox "Import fails:" & vbCrLf & Err.Description, vbCritical
End Sub

Sub O1_SortDataRowsByC()
    Call SortDataRows(3)
End Sub

Sub O1_ToggleAutoFilter()
    Call ToggleAutoFilter(6)
End Sub

Sub O1_AutoFitColumnWidth()
    Call AutoFitColumnWidth(3, 5)
End Sub