Flash cards
Review the key moves
What is the main idea behind CSS Legal Color Values?
Lesson checks
Practice each idea before moving on
Short Mimo-style checks built from this lesson's code, terms, and sequence.
Which statement best captures the main point of this lesson?
Complete the missing token from the example code.
#p1 {___-color: #ff0000;} /* red */Put the learning moves in the order that makes the concept easiest to apply.
CSS Colors
Colors in CSS can be specified by the following methods:
- Hexadecimal colors
- Hexadecimal colors with transparency
- RGB colors
- RGBA colors
- HSL colors
- HSLA colors
- Predefined/Cross-browser color names
- With the currentcolor keyword
Hexadecimal Colors
A hexadecimal color is specified with: #RRGGBB, where the RR (red), GG (green) and BB (blue) hexadecimal integers specify the components of the color. All values must be between 00 and FF.
For example, the #0000ff value is rendered as blue, because the blue component is set to its highest value (ff) and the others are set to 00.
Example
#p1 {background-color: #ff0000;} /* red */
#p2 {background-color: #00ff00;} /* green */
#p3 {background-color: #0000ff;} /* blue */Live preview
Hexadecimal Colors With Transparency
A hexadecimal color is specified with: #RRGGBB. To add transparency, add two additional digits between 00 and FF.
Example
#p1a {background-color: #ff000080;} /* red transparency */
#p2a {background-color: #00ff0080;} /* green
transparency */
#p3a {background-color: #0000ff80;} /* blue
transparency */Live preview
RGB Colors
An RGB color value is specified with the rgb() function , which has the following syntax:
rgb(red, green, blue)
Each parameter (red, green, and blue) defines the intensity of the color and can be an integer between 0 and 255 or a percentage value (from 0% to 100%).
For example, the rgb(0,0,255) value is rendered as blue, because the blue parameter is set to its highest value (255) and the others are set to 0.
Also, the following values define equal color: rgb(0,0,255) and rgb(0%,0%,100%).
Example
#p1 {background-color: rgb(255, 0, 0);} /* red */
#p2 {background-color: rgb(0, 255, 0);} /* green */
#p3 {background-color: rgb(0, 0, 255);} /* blue */Live preview
RGBA Colors
RGBA color values are an extension of RGB color values with an alpha channel - which specifies the opacity of the object.
An RGBA color is specified with the rgba() function , which has the following syntax:
rgba(red, green, blue, alpha)
The alpha parameter is a number between 0.0 (fully transparent) and 1.0 (fully opaque).
Example
#p1 {background-color: rgba(255, 0, 0, 0.3);} /* red with opacity */
#p2 {background-color: rgba(0, 255, 0, 0.3);} /* green with opacity */
#p3 {background-color: rgba(0, 0, 255, 0.3);} /* blue with opacity */Live preview
HSL Colors
HSL stands for hue, saturation, and lightness - and represents a cylindrical-coordinate representation of colors.
An HSL color value is specified with the hsl() function , which has the following syntax:
hsl(hue, saturation, lightness)
Hue is a degree on the color wheel (from 0 to 360) - 0 (or 360) is red, 120 is green, 240 is blue. Saturation is a percentage value; 0% means a shade of gray and 100% is the full color. Lightness is also a percentage; 0% is black, 100% is white.
Example
#p1 {background-color: hsl(120, 100%, 50%);} /* green */
#p2 {background-color: hsl(120, 100%, 75%);} /* light green */
#p3 {background-color: hsl(120, 100%, 25%);} /* dark green */
#p4 {background-color: hsl(120, 60%, 70%);} /* pastel green */Live preview
HSLA Colors
HSLA color values are an extension of HSL color values with an alpha channel - which specifies the opacity of the object.
An HSLA color value is specified with the hsla() function , which has the following syntax:
hsla(hue, saturation, lightness, alpha)
The alpha parameter is a number between 0.0 (fully transparent) and 1.0 (fully opaque).
Example
#p1 {background-color: hsla(120, 100%, 50%, 0.3);} /* green with opacity */
#p2 {background-color: hsla(120, 100%, 75%, 0.3);} /* light green with opacity */
#p3 {background-color: hsla(120, 100%, 25%, 0.3);} /* dark green with opacity */
#p4 {background-color: hsla(120, 60%, 70%, 0.3);} /* pastel green with opacity */Live preview
Predefined/Cross-browser Color Names
140 color names are predefined in the HTML and CSS color specification.
For example: blue , red , coral , brown , etc:
Example
#p1 {background-color: blue;}
#p2 {background-color: red;}
#p3 {background-color: coral;}
#p4 {background-color: brown;}Live preview
A list of all predefined names can be found in our Color Names Reference .
The currentcolor Keyword
The currentcolor keyword refers to the value of the color property of an element.
Example
#myDIV {
color: blue; /* Blue text color */
border: 10px solid currentcolor;
/* Blue border color */
}Live preview