local Lighting = game:GetService("Lighting")
local RunService = game:GetService("RunService")
local TweenService = game:GetService("TweenService")

local sky = Lighting:FindFirstChild("Sky")

local ROTATION_SPEED = 4 -- 1秒あたりの度数
local MAX_TILT = 2 -- 度
local TILT_SPEED = 4

local currentTilt = Instance.new("NumberValue")
currentTilt.Value = -MAX_TILT

local tweenGoal = { Value = MAX_TILT }
local tweenInfo = TweenInfo.new(TILT_SPEED, Enum.EasingStyle.Cubic, Enum.EasingDirection.InOut, -1, true)
local tween = TweenService:Create(currentTilt, tweenInfo, tweenGoal)
tween:Play()

RunService.Heartbeat:Connect(function(deltaTime)
	sky.SkyboxOrientation =
		Vector3.new(currentTilt.Value, (sky.SkyboxOrientation.Y + ROTATION_SPEED * deltaTime) % 360, 0)
end)