代码生成十二秒发布动画：打字、胶片与翻页书

Make a 12s motion video in code (1920x1080, 30fps, one HTML file drawing every frame from a single seek(t) function, rendered with Playwright + ffmpeg, with original synthesized sound).

Story: a dark prompt pill on an off-white page types "make a launch video" with a real keystroke rhythm → enter, the button flashes orange and the pill slides up → a 12-frame filmstrip stamps in left to right, one frame per beat at 120 BPM; each frame shows one pose of an orange ball's bounce (squash on contact, stretch mid-air, real arcs) → a playhead sweeps the strip while a big viewer above plays the poses as a flipbook, twice, faster the second time → the strip slides away, "every frame is code." fills the screen, and the ball arcs over and lands as the period.

Rules: arrive fast, land soft (cover 12–19% of the remaining distance per frame); nothing ever freezes (slow push on every hold); stagger 2–4 frames; blur only on fast moves; big and readable on a phone; off-white, ink and one orange only. Sound: a tick per key, a click on enter, a rising note per frame stamp, a thump when the ball lands.

Show me 5 stills first (typing, strip half-built, flipbook, headline, last frame), critique them like a harsh motion director, fix the 3 worst problems, then render.