2x2

a b
c d

Header row

a b
c d
e f

Header column

a b
c d
e f

Header row + column

a b
c d
e f

Color on top of header row

yr r
y
y

Color on top of header row + column

g o
g o
g o

Gray & brown on top of header row + column

g o
g o
g o