Gravity Flux Flappy Engine

I want you to act as a top-tier physics-based gameplay programmer. Produce a SINGLE FILE (index.html) build of an architectural flight evasion game.

GAME SPEC:

Title: Gravity Flux

Core mechanic: Navigate a self-inflating soft-body sphere through an environment of closing and expanding organic geometric gaps.

Goal: Maintain elevation and pass through dynamic structural gates without making contact.

TECH REQUIREMENTS:

Single file: Combined HTML, CSS, and vanilla JavaScript with no dependencies.

Rendering: 2D Canvas API. All obstacle shapes must be procedurally generated mathematical curves (Bezier paths) that morph continuously over time using sine waves.

Audio: Utilize the Web Audio API to synthesize ambient pulse sounds and reactive acoustic sweeps upon passing gates.

Design style: Zen-like abstract art style. Uses a monochromatic pastel palette with deep soft shadows (shadowBlur on canvas) to emphasize spatial depth and fluid motion.