Flash cards
Review the key moves
What is the main idea behind CSS RGB Colors?
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?
Put the learning moves in the order that makes the concept easiest to apply.
RGB Value
An RGB color value represents RED, GREEN, and BLUE light sources.
In CSS, a color can be specified as an RGB value, using this formula:
rgb( red, green , blue )
Each parameter (red, green, and blue) defines the intensity of the color between 0 and 255.
For example, rgb(255, 0, 0) is displayed as red, because red is set to its highest value (255) and the others are set to 0.
To display black, set all color parameters to 0, like this: rgb(0, 0, 0).
To display white, set all color parameters to 255, like this: rgb(255, 255, 255).
Experiment by mixing the RGB values below:
RED
GREEN
BLUE
Example
Shades of gray are often defined using equal values for all the 3 light sources:
RGBA Value
RGBA color values are an extension of RGB color values with an alpha channel - which specifies the opacity for a color.
An RGBA color value is specified with:
rgba( red, green , blue, alpha )
The alpha parameter is a number between 0.0 (fully transparent) and 1.0 (not transparent at all):
Experiment by mixing the RGBA values below:
RED
GREEN
BLUE
ALPHA