Intervals to guess: b2 (flat 2nd), 2 (major 2nd), b3 (flat 3rd), 3 (major 3rd), 4 (perfect 4th), b5 (flat 5th/tritone), 5 (perfect 5th), b6 (flat 6th), 6 (major 6th), b7 (flat 7th), 7 (major 7th), octave.

Type "b" for flat (e.g., "b3").

IMPORTANT: This game requires acoustic guitar audio samples (e.g., `48.wav`, `49.wav` etc.) in a `guitar_samples` folder next to this HTML file.