Example:
# Instantiating a Workbook object
workbook = Workbook()
cells = workbook.getWorksheets().get(0).getCells()
cells.get("A1").putValue("Hello World")
style = cells.get("A1").getStyle()
# Set ThemeColorType.Text2 color type with 40% lighten as the font color.
style.getFont().setThemeColor(ThemeColor(ThemeColorType.TEXT_2, 0.4))
style.setPattern(BackgroundType.SOLID)
# Set ThemeColorType.Background2 color type with 75% darken as the foreground color
style.setForegroundThemeColor(ThemeColor(ThemeColorType.BACKGROUND_2, -0.75))
cells.get("A1").setStyle(style)
# Saving the Excel file
workbook.save("Book1.xlsx")