local flying = false
local speed = 2
local RunService = game:GetService("RunService")
local UIS = game:GetService("UserInputService")

local bv, bg

local function startFly()
    local char = player.Character
    local hrp = char and char:FindFirstChild("HumanoidRootPart")
    if not hrp then return end

    bv = Instance.new("BodyVelocity", hrp)
    bv.MaxForce = Vector3.new(1,1,1) * 1e9
    bv.Velocity = Vector3.zero

    bg = Instance.new("BodyGyro", hrp)
    bg.MaxTorque = Vector3.new(1,1,1) * 1e9
    bg.CFrame = hrp.CFrame

    RunService:BindToRenderStep("Fly", 0, function()
        local cam = workspace.CurrentCamera
        local dir = Vector3.zero

        if UIS:IsKeyDown(Enum.KeyCode.W) then dir += cam.CFrame.LookVector end
        if UIS:IsKeyDown(Enum.KeyCode.S) then dir -= cam.CFrame.LookVector end
        if UIS:IsKeyDown(Enum.KeyCode.A) then dir -= cam.CFrame.RightVector end
        if UIS:IsKeyDown(Enum.KeyCode.D) then dir += cam.CFrame.RightVector end
        if UIS:IsKeyDown(Enum.KeyCode.Space) then dir += Vector3.new(0,1,0) end
        if UIS:IsKeyDown(Enum.KeyCode.LeftControl) then dir -= Vector3.new(0,1,0) end

        bv.Velocity = dir * 60
        bg.CFrame = cam.CFrame
    end)
end

local function stopFly()
    RunService:UnbindFromRenderStep("Fly")
    if bv then bv:Destroy() end
    if bg then bg:Destroy() end
end

flyBtn.MouseButton1Click:Connect(function()
    flying = not flying
    flyBtn.Text = flying and "FLY: ON" or "FLY: OFF"
    if flying then
        startFly()
    else
        stopFly()
    end
end)