# Dub Techno Sequencer with Tape Deck Controls

## Overview
Build a browser-native audio workstation in a single `index.html` file. The theme is a dub techno sequencer with tape deck aesthetics. It must be interactive, playable with both mouse and touch, and use only the Web Audio API — no external media assets.

## Functional Requirements
1. Sequencer grid: **6 tracks × 16 steps**.
   - Step toggle by click/tap.
   - Running playhead indicator.
2. **Transport controls** in tape deck style:
   - Large Play/Stop/Record buttons with cassette-inspired icons.
   - BPM control with a large slider (range **60–160 BPM**) and a digital-style display.
   - Tape counter readout that increments during playback.
3. **At least 3 distinct voices/tracks** synthesized via Web Audio API:
   - **Kick**: Sine sweep with fast pitch envelope.
   - **Snare/Clap**: Noise burst with bandpass and amplitude envelope.
   - **Hi-hat**: High-frequency noise with sharp decay.
   - **Bass**: Detuned saw/square with low-pass filter, dub-style.
   - **Stab/Pad**: FM-style or filtered chord stabs for atmosphere.
   - **Ghost Hit**: Noise for subtle percussive texture.
4. **Per-track controls**:
   - Large Mute toggle buttons.
   - Volume sliders.
   - **Delay Send** knob — a hallmark of dub techno, feeding into a feedback delay network.
5. **Dub Delay Engine**:
   - Shared stereo delay node with filtered feedback.
   - Per-track wet/dry mix via the delay send.
6. **Visual polish**:
   - Dark, cassette-inspired aesthetic.
   - Large touch targets for mobile.
   - VU-meter-style track activity indicators during playback.
   - Subtle tape wobble visual cue when playing.

## Technical Constraints
- Single self-contained `index.html` file.
- No external images, audio, or video. Use inline SVG for icons and Canvas for any visual meters.
- Use the Web Audio API directly; no CDN libraries.
- Support Chromium, Safari, and Firefox.
- Ensure audio context resumes on first gesture per browser autoplay policies.

## Output
Return the complete HTML file content.