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①The volume balance of background music and sound effects can be adjusted in fine increments of 10% each.

②You can also switch between window modes.
(With a keyboard, you can always use the F4 key to switch window mode.)
(Window mode can be selected from "Full Screen," "Window (Small)," and "Window (Large).")

③ If you clear hard mode, a sound test will be added!!!
You can listen to all the songs in the game plus the immortal songs!