Like i try to zoom up to my mouse with a gun so ya. This doesn't work.

sp = script.Parent


local player = game.Players.LocalPlayer
local mouse = player:GetMouse()


function zoom(key)
	key = key:lower()
	if key and key == "z" then
		local cam = game.Workspace:FindFirstChild("Camera")
		if cam then
			cam.Focus = CFrame.new(mouse, 0, 0)
		end
	end
end

mouse.KeyDown:connect(zoom)

Why won't it zoom up?