Animated cutaway of a nine-cylinder radial aircraft engine

GOAL: Build a 2D animated cutaway of a 9-cylinder radial aircraft engine called "RADIAL NINE" — a clean technical loop that shows how nine pistons share one crankshaft. MOTION: STYLE (strict) Flat 2D technical front view on a deep navy background (#0b1220 or similar), like a premium engineering explainer. Clean shapes with soft shading, thin light outlines, a subtle hatched pattern on cut metal walls. Palette: light steel-grey metal; fresh fuel-air mixture in blue; combustion in orange to white; exhaust in smoky grey. One square composition (1:1), the engine centred and filling ~80% of the square. NO on-screen UI, no title, no labels by default. The only text is small cylinder numbers 1–9 engraved on the cylinder heads as part of the drawing. THE ENGINE (must be mechanically correct) Front view, with the propeller drawn as a faint translucent blur so the engine behind it stays visible. Nine finned cylinders spaced evenly every 40° around a round crankcase, each cut open to show its piston. Every cylinder head has an intake and an exhaust valve with rocker arms and pushrods. A single-throw crankshaft in the centre. One master rod on cylinder 1 is attached directly to the crank pin; the other eight articulated link rods attach to pins on the master rod's big end, not to the crankshaft. Because of the articulated rods, the pistons' motion is slightly non-uniform. Model the real linkage geometry rather than faking it with identical sine motion. Four-stroke cycle: each cylinder fires once every two crankshaft revolutions. Firing order 1-3-5-7-9-2-4-6-8, so the flashes jump around the ring skipping every other cylinder. THE CYCLE (driven by one crank angle, all motion synchronized) Intake: the intake valve opens and blue mixture flows in as the piston moves inward. Compression: both valves closed, the mixture compresses and brightens. Power: a spark and an orange flame front fill the cylinder and push the piston inward. Exhaust: the exhaust valve opens and grey exhaust leaves through the exhaust stub. Rockers and pushrods move in time with their valves. Gases never pass through solid walls. ANIMATION (starts on load) Seamless loop of ~10–12 s at a readable speed (about one crankshaft revolution every 1.5 s), so the firing pattern reads as a spiral of flashes. A brief 0.5× slow-down once per loop so the articulated rods can be followed. Subtle heat glow on each cylinder head after it fires, slight engine vibration, the propeller blur spinning in sync with the crankshaft. KEYBOARD (optional, nothing visible on screen) Space pauses, S toggles slow motion, L toggles small labels (master rod, link rod, crank pin, intake, exhaust, spark plug), arrow keys change speed. TECHNICAL Canvas or SVG, any libraries you like (loaded from a CDN). Everything works by opening index.html directly in the browser: no build step, no local server. Starts automatically on load, no Start button. Smooth 60 fps. The square stays centred and as large as possible at any window size, inc