Closest hex to #b3181c is #b12

Minify your CSS by half!

#
#b12

b3181c

b3181c

contains b1

0b1 1b1 2b1 3b1 4b1 5b1 6b1 7b1 8b1 9b1 ab1 b10 b11 b12 b13 b14 b15 b16 b17 b18 b19 b1a b1b b1c b1d b1e b1f bb1 cb1 db1 eb1 fb1

contains 12

012 112 120 121 122 123 124 125 126 127 128 129 12a 12b 12c 12d 12e 12f 212 312 412 512 612 712 812 912 a12 b12 c12 d12 e12 f12

contains b2

0b2 1b2 2b2 3b2 4b2 5b2 6b2 7b2 8b2 9b2 ab2 b20 b21 b22 b23 b24 b25 b26 b27 b28 b29 b2a b2b b2c b2d b2e b2f bb2 cb2 db2 eb2 fb2