012 Magnetic Filings

1 test · 10 finished runs (0 agent, 10 raw one-shot) · 10 live demos

The prompt

Magnetic Filings: Thousands of short iron-filing strokes on a pale background align to the field of two draggable magnets, one red north and one blue south. Strokes recompute live as magnets are dragged; a double click adds a third magnet and a button flips each polarity. Build it as ONE self-contained HTML file: inline CSS and JavaScript only, no libraries or frameworks, and no external requests of any kind (no CDNs, web fonts, images or audio files); anything visual or audible is made in code (HTML/CSS, SVG, Canvas, WebGL or WebAudio). It must work when opened directly from disk, fit the browser window responsively, and run without console errors. Output ONLY the complete HTML file, starting with <!DOCTYPE html> and ending with </html>, with no explanation or markdown fences.