... color value that takes three arguments, with a similar syntax to RGB:E { color: hsl(hue,saturation,lightness); }Hue accepts a value of 0 to 360, and saturation and lightness accept values from ... hidden.The second example shows three radial gradients with a radius of 50px each. Again, the to- stop has a value of transparent to allow the layers below to show through.Repeating Gradients in FirefoxOne ... colors, as well as the introduction of opacity through the Alpha channel.The Alpha ChannelThe Alpha channel (Alpha for short) is the measure of the transparency of a color—as opposed to the opacity...