The user wants me to build a single-page web app that:
1. Uses the provided tone.min.js library (global Tone)
2. Has a clickable pentatonic pad grid that triggers a synth voice with reverb
3. Has a play/stop button that runs an arpeggiator sequence at an adjustable tempo
4. All sound synthesized, no audio files
5. Everything in one index.html file

Let me create this step by step. I'll need to:
1. Create a pentatonic scale (e.g., C pentatonic: C, D, E, G, A)
2. Create a grid of pads (maybe 5x5 or something similar)
3. Each pad triggers a synth note when clicked
4. Add reverb effect
5. Create an arpeggiator that plays through the pentatonic scale
6. Add play/stop button and tempo control

Let me write this all in a single index.html file.

I've created a complete single-page web app with:

1. A pentatonic pad grid (25 pads covering 5 octaves of C Major Pentatonic scale)
2. A synth voice using Tone.js PolySynth with sine wave oscillator
3. Reverb effect that's adjustable
4. Play/Stop button for the arpeggiator
5. Adjustable tempo control (60-200 BPM)
6. Visual feedback on both the pads and an arpeggiator display
7. Keyboard support (QWERTY rows map to the first 3 rows of pads)
8. Touch support for mobile devices
9. A start notice that handles the browser's autoplay policy
10. Beautiful styling with gradients and animations

All in one self-contained index.html file that loads the provided tone.min.js library.