How to slowly shift BrickColor?

I have an model where all descendants called Part need to slowly shift color, here's the code I already have:

items = {}

for index, descendant in pairs(script.Parent.Model:GetDescendants()) do
	if descendant.Name == "Part" then
		table.insert(items, descendant)
	end
end

while true do
	for i, v in items do
		-- What do I do now?
	end
	
	wait(math.random(0.95, 1.05)) -- Stay as solid color for a very short while
end

I'd rather have my game run nice and smooth, but if no one knows how to make this code also smooth I'll just use the best other code I can find.

Here is the gist

local tween = function(Object, Changes)
	local Info = TweenInfo.new(
		.5, --Time to do the tween
		Enum.EasingStyle.Back, -- Style
		Enum.EasingDirection.Out, -- Direction
		0, -- number of repeats
		false, -- reverts back to normal
		0 -- Delay 
	)
	local TweenService = game:GetService("TweenService")
	local Action = TweenService:Create(Object, Info, Changes)
	return Action
end


while true do
	local Action = tween(script.Parent, {Color = Color3.fromRGB(math.random(0,255), math.random(0,255), math.random(0,255))})
	Action:Play()
	Action.Completed:Wait()
end

Put this in a brick

local colors = {BrickColor.new("Steel blue").Color, 
                BrickColor.new("Bright violet").Color,
                BrickColor.new("Magenta").Color,
                BrickColor.new("Neon orange").Color,
                BrickColor.new("Bright yellow").Color,
                BrickColor.new("Lime green").Color,
                BrickColor.new("Toothpaste").Color} -- the colors table, you change change them.

local tweenService = game:GetService("TweenService")

script.parent.Material = ("Neon") --The Mateiral

function ColorChange(colorToChangeTo) --color change function

	local time = 3 --Set this to the time
    local tweenInformation = TweenInfo.new(time) 
    local ColorProperty = {}

    ColorProperty.Color = colorToChangeTo

    local tween = tweenService:Create(script.Parent,tweenInformation,ColorProperty)
    tween:Play() --play tween

    wait(time)

end


while true do

    for i, v in ipairs(colors) do --colors

        ColorChange(v)      

    end

end
--https://gyazo.com/47c0a30384534f038b6b735cf07efc97

Nvm, I found a solution myself, it might now be the smoothest but I'm fine with it.

local items = {}

for index, descendant in pairs(script.Parent.Model:GetDescendants()) do
	if descendant.Name == "Part" then
		table.insert(items, descendant)
	end
end

function positify(val)
	if val < 0 then
		return -val
	else
		return val
	end
end

while true do
	local newR = math.random(255) / 255
	local newG = math.random(255) / 255
	local newB = math.random(255) / 255
	
	local running = true
	
	while running do
		for i, v in pairs(items) do
			if v.Color.r > newR then
				v.Color = Color3.new(v.Color.r - 1 / 255, v.Color.g, v.Color.b)
			elseif v.Color.r < newR then
				v.Color = Color3.new(v.Color.r + 1 / 255, v.Color.g, v.Color.b)
			end
			
			if v.Color.g > newG then
				v.Color = Color3.new(v.Color.r, v.Color.g - 1 / 255, v.Color.b)
			elseif v.Color.g < newG then
				v.Color = Color3.new(v.Color.r, v.Color.g + 1 / 255, v.Color.b)
			end
			
			if v.Color.b > newB then
				v.Color = Color3.new(v.Color.r, v.Color.g, v.Color.b - 1 / 255)
			elseif v.Color.b < newB then
				v.Color = Color3.new(v.Color.r, v.Color.g, v.Color.b + 1 / 255)
			end
			
			if positify(newR - v.Color.r) <= 1 / 255 then
				if positify(newG - v.Color.g) <= 1 / 255 then
					if positify(newB - v.Color.b) <= 1 / 255 then
						running = false
					end
				end
			end
		end
		
		wait()
	end
	
	wait(math.random(0.95, 1.05)) -- Stay as solid color for a very short while
end