Draw 12 steampunk baggy jumper variants as separate 1024x1024 RGBA PNG layers for a generative PFP collection. Character is FRONT-FACING (the eyes glance sideways, but the skull and torso face the viewer, symmetric about x=512).

Match the base exactly: painterly steampunk, fine dark ink outlines, grimy soft shading, palette of black/charcoal, deep teal, oxblood, mustard and ivory knit with tarnished brass accents (buttons, gear patches, riveted leather elbow or shoulder straps, chain pulls).

Flavour: oversized, slouchy, chunky-knit jumpers, sleeves hidden off-canvas. Mix crew necks, roll necks, quarter-zips with brass zippers, cable knits, patched and darned knits, and leather-yoked knits.

Placement: the layer sits ON TOP of a base that already wears a high-collared leather coat, so the jumper must be fully opaque and cover the whole torso: x=0..1024 down to the bottom edge y=1024.

Shoulder line: y≈870 at x=0 and x=1024, rising to y≈770 at x≈340 and x≈684.

Neckline: hug under the jawbone and never draw above it. The jaw outline runs from (360,760) down to the chin at (512,848) and back up to (664,760), so no jumper pixels may cross into that region. Neck opening ≈ x=380..644, lowest point y≈850 at x=512.

Roll necks may rise to the jaw outline but must never overlap the skull. Make the jumper bulky enough to hide the coat lapels at x≈215..330 and x≈694..810, y≈760..1000. Only the jumper pixels; everything else is fully transparent.

No skull, head, background, or shadows outside the garment.

Outputs: artifacts/jumper_01.png .. artifacts/jumper_12.png, plus artifacts/jumper.json, an array of {"file","name","weight"}. Weights are integers summing to 100, with rarer variants (brass-zip, gear-embroidered, leather-yoke) getting lower weights. Write artifacts/jumper_01.png .. artifacts/jumper_12.png and artifacts/jumper.json: an array of {"file","name","weight"} with weights summing to 100, rarer lower.