What color is Unknown ?

Source Crayola® CSS3 CSS4
#dbd9c6
 
#dbd7d2
timberwolf
#d3d3d3
light gray
#d3d3d3
lightgrey
#9c977f
 
#95918c
gray
#808080
grey
#808080
grey
#839a9f
 
#979aaa
manatee
#778899
light slate grey
#778899
lightslategrey
#515247
 
#414a4c
outer space
#556b2f
dark olive green
#556b2f
darkolivegreen
#6f7467
 
#757575
sonic silver
#696969
dim grey
#696969
dimgrey