TITLE: Infinite Coastline — Mandelbrot & Julia Explorer FILE: 042-fractal-explorer.html === PROMPT (exact prompt used) === Build "Infinite Coastline — Mandelbrot & Julia Explorer". A full-screen canvas rendering the Mandelbrot set with smooth (continuous) colouring and a choice of cyclic palettes: "Aurum" (black → deep blue → gold → white), "Abyss" (navy → cyan → white), "Magma" and "Pastel Dream". Render progressively (low-resolution preview, then refinement in chunks scheduled with requestAnimationFrame, optionally in a Web Worker created from an inline Blob) so the UI never freezes. Interaction: click/tap to zoom in on a point (animated); right-click or a button to zoom out; drag to pan; mouse-wheel zoom; and a live mini Julia-set window that follows the cursor showing the Julia set for the hovered c — press J to make it the main view. HUD: coordinates, zoom level and iteration count (rising automatically with zoom); bookmarks of famous locations (Seahorse Valley, Elephant Valley, a triple spiral, a mini-brot). Palette-cycling animation toggle. Download PNG. A sleek dark UI with thin gold typography. SHARED REQUIREMENTS (apply to every page in this 100-page collection): 1. One standalone HTML5 file. All CSS inline in