Summary

• Bug: Cancelling the background color picker dialog causes a NameError crash because text_area is only defined inside the if color: block but referenced outside it on the next line.
• Fix: Nest the text_area check inside the if color: block, matching the pattern already used by choose_fg_color().

Before (buggy)

if color:
    color = color.hex
    text_area = self.get_current_text_area()
if text_area:  # NameError if color is None
    text_area.config(bg=color)

After (fixed)

if color:
    color = color.hex
    text_area = self.get_current_text_area()
    if text_area:
        text_area.config(bg=color)
        self.current_bg_color = color
        self.update_preview()

Test plan

• Open the app, go to background color picker, cancel the dialog — should no longer crash
• Choose a valid color — should still apply correctly