917bccba ​

input = fill 12v (fill 12h black) |> rect ((#1.1 - 1, #1.2 - 1, #1.3 + 1, #1.4 + 1), #0) |> rect (#1, #2) |> fold (λr. rect (r, #2)) #3 |> fold (λr. rect (r, black)) #4
output = fill 12v (fill 12h black) |> rect ((#1.1 - 1, #1.2 - 1, #1.3 + 1, #1.4 + 1), #0) |> fold (λr. rect ((#1.1 - 1, r.1, #1.1 - 1, r.2), #2)) #5 |> fold (λr. rect ((r.1, #1.4 + 1, r.2, #1.4 + 1), #2)) #6 |> rect (#1, black)
(Color, (VInt, HInt, VInt, HInt), Color, UList (VInt, HInt, VInt, HInt), UList (VInt, HInt, VInt, HInt), UList (HInt, HInt), UList (VInt, VInt))
(red, (4v, 4h, 7v, 7h), green, {(9v, 5h, 12v, 5h), (6v, 9h, 6v, 12h), (6v, 1h, 6v, 2h), (1v, 5h, 2v, 5h)}, {(7v, 6h, 7v, 7h), (7v, 4h, 7v, 4h), (4v, 6h, 5v, 7h), (4v, 4h, 5v, 4h)}, {(9h, 12h), (1h, 2h)}, {(9v, 12v), (1v, 2v)})
(blue, (5v, 4h, 9v, 8h), teal, {(11v, 6h, 12v, 6h), (7v, 10h, 7v, 12h), (7v, 1h, 7v, 2h), (1v, 6h, 3v, 6h)}, {(8v, 7h, 9v, 8h), (8v, 4h, 9v, 5h), (5v, 7h, 6v, 8h), (5v, 4h, 6v, 5h)}, {(10h, 12h), (1h, 2h)}, {(11v, 12v), (1v, 3v)})
(green, (5v, 6h, 7v, 8h), yellow, {(9v, 7h, 12v, 7h), (6v, 10h, 6v, 12h), (6v, 1h, 6v, 4h), (1v, 7h, 3v, 7h)}, {(7v, 8h, 7v, 8h), (7v, 6h, 7v, 6h), (5v, 8h, 5v, 8h), (5v, 6h, 5v, 6h)}, {(10h, 12h), (1h, 4h)}, {(9v, 12v), (1v, 3v)})
(orange, (4v, 4h, 9v, 9h), fuschia, {(11v, 7h, 12v, 7h), (6v, 11h, 6v, 12h), (6v, 1h, 6v, 2h), (1v, 7h, 2v, 7h)}, {(7v, 8h, 9v, 9h), (7v, 4h, 9v, 6h), (4v, 8h, 5v, 9h), (4v, 4h, 5v, 6h)}, ?, ?)