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Conoscere i CSS:Colori

This page explains more about 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. CSS 2 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 


<caption style="font-weight:bold; text-align:left;">More details </caption>
Your broswer 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 hexadcimal 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.

<caption style="font-weight:bold; text-align:left;">Examples </caption>
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


<caption style="font-weight:bold; text-align:left;">More details </caption>
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 for 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.

<caption style="font-weight:bold; text-align:left;">Example </caption>
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

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

/*** CSS Tutorial: Color page ***/
 
/* page font */
body {font: 16px "Comic Sans MS", cursive;}
 
/* paragraphs */
p {color: blue;}
#first {font-style: italic;}
 
/* initial letters */
strong {
  color: red;
  background-color: #ddf;
  font: 200% serif;
  }
 
.carrot {color: red;}
.spinach {color: green;}

Refresh your browser to see the result:

Cascading Style Sheets
Cascading Style Sheets


<caption style="font-weight:bold; text-align:left;">Challenge </caption>
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.)


What next?

Your sample document and your sample stylesheet strictly separate content from style.

The next page explains how you can make exceptions to this strict separation: Content

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