These have been chosen to be similar to many real-world monitors and viewing conditions, to allow rendering to be fairly close to the specified values even without color management. Web colors have an unambiguous colorimetric definition, sRGB, which relates the chromaticities of a particular phosphor set, a given transfer curve, adaptive whitepoint, and viewing conditions. The first versions of Mosaic and Netscape Navigator used the X11 color names as the basis for their color lists, as both started as X Window System applications. It is impossible with the hexadecimal syntax (and thus impossible in legacy HTML documents that do not use CSS). Specifying a non-sRGB color this way requires the RGB() function call. Thus, there are 24 bits used to specify a web color within the sRGB gamut, and 16,777,216 colors that may be so specified.Ĭolors outside the sRGB gamut can be specified in Cascading Style Sheets by making one or more of the red, green and blue components negative or greater than 100%, so the color space is theoretically an unbounded extrapolation of sRGB similar to scRGB. A color is specified according to the intensity of its red, green and blue components, each represented by eight bits. In some uses, hexadecimal color codes are specified with notation using a leading number sign (#). A color tool or other graphics software is often used to generate color values. Colors may be specified as an RGB triplet or in hexadecimal format (a hex triplet) or according to their common English names in some cases. Web colors are colors used in displaying web pages on the World Wide Web, and the methods for describing and specifying those colors.

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