Color

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Text stylesThis is the 8th section of the CSS Getting Started tutorial; it explains how you can specify color in CSS. In your sample stylesheet, you introduce background colors.

Information: Color

In this tutorial so far, you have used a limited number of named colors. CSS2 supports 17 named colors in all. Some of the names might not be what you expect:

black

gray

silver

white

primaries

red

lime

blue

secondaries

yellow

aqua

fuchsia

maroon

orange

olive

purple

green

navy

teal

Details

Your browser might support many more named colors, like:

dodgerblue

peachpuff

tan

firebrick

aquamarine

For details of this extended list, see: SVG color keywords in the CSS 3 Color Module. Beware of using color names that your reader's browsers might not support.

For a larger palette, specify the red, green and blue components of the color you want by using a number sign (hash) and three hexadecimal digits in the range 0 – 9, a – f. The letters a – f represent the values 10 – 15:

black		`#000`
pure red		`#f00`
pure green		`#0f0`
pure blue		`#00f`
white		`#fff`

For the full palette, specify two hexadecimal digits for each component:

black		`#000000`
pure red		`#ff0000`
pure green		`#00ff00`
pure blue		`#0000ff`
white		`#ffffff`

You can usually get these six-digit hexadecimal codes from your graphics program or some other tool.

Example

With a little practice, you can adjust the three-digit colors manually for most purposes:

Start with pure red:		`#f00`
To make it paler, add some green and blue:		`#f77`
To make it more orange, add a little extra green:		`#fa7`
To darken it, reduce all its components:		`#c74`
To reduce its saturation, make its components more equal:		`#c98`
If you make them exactly equal, you get gray:		`#ccc`

For a pastel shade like pale blue:

Start with pure white:		`#fff`
Reduce the other components a little:		`#eef`

More details

You can also specify a color using decimal RGB values in the range 0 – 255, or percentages.

For example, this is maroon (dark red):

rgb(128, 0, 0)

For full details of how to specify colors, see: Colors in the CSS Specification.

For information on matching system colors like Menu and ThreeDFace, see: CSS2 System Colors in the CSS Specification.

Color properties

You have already used the color property on text.

You can also use the background-color property to change elements' backgrounds.

Backgrounds can be set to transparent to explicitly remove any color, revealing the parent element's background.

Example

The Example boxes in this tutorial use this pale yellow background:

background-color: #fffff4;

The More details boxes use this pale gray:

background-color: #f4f4f4;

Action: Using color codes

Color page

Edit your CSS file.
Make the change shown down here, to give the initial letters a pale blue background. (The layout and comments in your file probably differ from the file shown here. Keep the layout and comments the way you prefer them.)

HTML Content

<p id = "first"> <strong>C</strong>ascading <strong class="spinach">S</strong>tyle <strong class="spinach">S</strong>heets</p>
<p> <strong>C</strong>ascading <strong>S</strong>tyle <strong>S</strong>heets</p>

CSS Content

/*** CSS Tutorial: Color page ***/

/* page font */
body {
  font: 16px "Comic Sans MS", cursive;
}

/* paragraphs */
p {
  color: blue;
}
#first {
  font-style: italic;
}

/* initial letters */
strong {
  background-color: #ddf; 
  color: red;
  font: 200% serif;
}

.spinach {
  color: green;
  background-color: #ddf;
}

Save the file and refresh your browser to see the result.
The result should be like this:

Challenge

In your CSS file, change all the color names to 3-digit color codes without affecting the result.

(This cannot be done exactly, but you can get close. To do it exactly you need 6-digit codes, and you need to look up the CSS Specification or use a graphics tool to match the colors.)

Possible solution

The following values are reasonable approximations of the named colors:

strong {
  color: #f00; /* red */
  background-color: #ddf; /* pale blue */
  font: 200% serif;
}

.carrot {
  color: #fa0; /* orange */
}

.spinach {
  color: #080; /* dark green */
}

p {
  color: #00f; /* blue */
}

Hide solution

See a solution for the challenge.

What next?

Перейти к следующему разделу:
ContentYour sample document and your sample stylesheet strictly separate content from style. The next section explains how you can make exceptions to this strict separation.