Run it
Copy the script and paste it into your executor.
local Light = game:GetService("Lighting")
function dofullbright()
Light.Ambient = Color3.new(1, 1, 1)
Light.ColorShift_Bottom = Color3.new(1, 1, 1)
Light.ColorShift_Top = Color3.new(1, 1, 1)
end
dofullbright()
Light.LightingChanged:Connect(dofullbright)As shown in image

Universal