Nested 3 Multicols Fixed Height

Below there should be a multicol inside a multicol inside a multicol.

The innermost multicol (papayawhip, thin column rules) should have a total of eight columns and consist of twelve lines. Each line should have a letter, from A to L, ascendingly.

The middle multicol (salmon, medium column rules) should have four columns. The first line in the first line should say "middle first". Then comes the inner multicol, followed by the last line in the last column, which should say "middle last".

The outermost multicol (lime, thick column rules) should have two columns. The first line in the first column should say "outer first". Then comes the middle (and inner) multicol, followed by the last line in the last column, which should say "outer last".

Rules should be drawn between columns in the same row.

outer first middle first A
B
C
D
E
F
G
H
I
J
K
L

middle last outer last