In CSS, a color can be specified in several ways, and can apply not just to text but also borders, ALT text, bullet points and ordered lists.
where RR (red), GG (green) and BB (blue) are hex color numbers ranging between 0 and FF.
e.g. color: #ffffff; /* pure white */
Where each parameter (red, green, and blue) can be an integer between 0 and 255 or a percentage value (from 0% to 100%).
e.g. color: rgb(255,0,0);
Full list of the Extended color keywords supported by popular browsers (W3.org)
e.g. color: red;
In addition to the above there is a new RGBA color format, only supported by more recent web browsers (IE9+, Firefox 3+, Chrome, Safari, Opera 10+):
An RGBA value color
The alpha channel specifies the opacity of the object, a number between 0.0 (fully transparent) and 1.0 (fully opaque).
RGBA sets the opacity value only for a single element. unlike opacity which sets the opacity for an element and all of its children.
To deal with older browsers that don't understand RGBA, specify a simple color as a fallback before the RGBA rule:
This is a line of sample text we can apply CSS colors to. The background color will also affect the perception and readability of color text.
(CSS 1) Browser Support: All major browsers.
“Speed kills colour... the gyroscope, when turning at full speed, shows up gray” ~ Paul Morand