How do I tween GUI backgroundtransparency?

I am trying to get the GUI’s background transparency to tween but it’s not working?

I do not know how to tween can someone help?

Script:

local tweenService = game:GetService("TweenService")
local black = script.Parent:WaitForChild("Black")
local test = black.Test
local tweenInformation = TweenInfo.new(3,Enum.EasingStyle.Quart,Enum.EasingDirection.In,1,false,0)
local blackdisappear = {BackGroundTransparency = 1}
local testdisappear = {TextTransparency = 1}
local blackInfo = tweenService:Create(black,tweenInformation,blackdisappear)
local testInfo = tweenService:Create(test,tweenInformation,testdisappear)

wait(6)


blackInfo:Play()
testInfo:Play()

You spelled the term incorrectly, it should be:

local blackdisappear = {BackgroundTransparency = 1}