Les fonctions pour les couleurs rgb

• rgb($red, $green, $blue) - Creates a Color from red, green, and blue values.
• rgba($red, $green, $blue, $alpha) - Creates a Color from red, green, blue, and alpha values.
• red($color) - Gets the red component of a color.
• green($color) - Gets the green component of a color.
• blue($color) - Gets the blue component of a color.
• mix($color-1, $color-2, [$weight]) - Mixes two colors together.