Head First HTML with CSS

understanding hex codes
The two minute guide to hex codes
The first thing you need to know about hex codes is that they aren’t based on ten
digits (0 to 9) – they’re based on 16 digits (0 to F). Here’s how hex digits work:
1
0
2
3
4
370 Chapter 9
5
6
7 8
9
A
10
B
11
C
12
D
13
E
14
15
F
So if you see a hex number like B, you know that just means 11. But, what does BB,
or E1, or FF mean? Let’s disassemble a hex color and see what it actually represents.
In fact, here’s how you can do that for any hex color you might encounter.
Step one:
Separate the hex color into its three components.
Remember that each hex color is made up of a red, green and blue component.
The first thing you want to do is separate those.
# CC66 00
Red
CC
Green
66
Blue
00
Using hex, you only need a single
digit to count all the way from
0 to 15. When you get above 9,
you start using letters.
Take your hex color and
break it up into its red,
green, and blue components.