11ty Color Picker
RGB: The RGB cubic-coordinate system can use either hexadecimal color codes or
rgb(red, green, blue). The values for each red, green, blue channel can range from 0-255. The notation for specifying RGB colors is
rgb(240, 30, 200).
Hex: Hexadecimal color codes are expressed as a six-digit combination of numbers and letters defined by it's mix of red, green and blue (RGB). Hexademical colors can be used like
#ff0066 using six-digits or in a more shorthand form using only three-digits
#f06. The three digit hex colors are expanded to six-digits by doubling each digit.
HSL: The HSL cylindrical-coordinate system stands for hue, saturation and lightness. A hue value can range from 0-360 and saturation/lightness can range from 0% to 100%. The syntax for using HSL is
hsl(hue, saturation, lightness) so a valid value would look like
hsl(300, 100%, 25%).
Read more about color values on MDN.