14.3 Document Color Properties
Each of these color properties has a string value. To set a color, you can use one of the predefined HTML color names, or you can specify the color as red, green, and blue color values, expressed as a string of six hexadecimal digits in the form #RRGGBB. You may recall that Example 13-7 set the bgcolor attribute of the <body> tag to a color string expressed in this fashion.
In the W3C DOM standard, the color properties of the Document object are deprecated in favor of properties of the Element object that represents the <body> tag. Furthermore, the HTML 4 standard deprecates the color attributes of the <body> tag in favor of CSS style sheets. What this means is that you probably should not write scripts that rely heavily on these doubly deprecated color properties!