jquery - Modify a string in JavaScript -

i want modify color attribute returned in jquery. so, lets assume color returned , contained in

var color color = 'rgb(148, 141, 124)'

i want modify value of color be:

color = 'rgb(148, 141, 124, .7)'

(in other words, insert string ", .7")

you below:

color = color.replace(/\)/, ', 0.7)')

My