TITLE: Lines of Force — Magnetic Field Explorer FILE: 095-magnetic-field.html === PROMPT (exact prompt used) === Create "Lines of Force — Magnetic Field Explorer". A lab-styled canvas where you place and drag bar magnets (red N / blue S halves, #d62828 / #1d4e89) on a sheet of paper; the field is computed from magnetic dipoles (or magnetic charges at the poles) and rendered in three switchable styles: (1) iron filings — thousands of tiny dark filings aligned with the field, denser where it is stronger, like the classic school experiment on off-white paper; (2) field lines — smooth streamlines traced from the poles with arrowheads, in elegant ink; (3) a heat map of field magnitude in a refined sequential palette. A small compass follows the pointer and points along the field. Interaction: drag magnets; rotate with the wheel, R key or a handle; double-click to flip polarity; add/remove magnets; presets (single bar, attracting pair, repelling pair, quadrupole, horseshoe). Short explanatory captions in a sidebar. Palette: steel grey #6c757d, paper #f8f6f1, red/blue poles. Typography: a clean scientific sans. SHARED REQUIREMENTS (apply to every page in this 100-page collection): 1. One standalone HTML5 file. All CSS inline in