local Players = game:GetService("Players")
local UserInputService = game:GetService("UserInputService")
local RunService = game:GetService("RunService")

local LocalPlayer = Players.LocalPlayer
local PlayerGui = LocalPlayer:WaitForChild("PlayerGui")

-- Global Variables
local money = 0                      -- current money
local steps = 0                      -- step counter
local multiplier = 1                 -- initial multiplier
local rebirthCost = 50               -- cost of first rebirth
local taxRarity = 1/4                -- rarity of tax payment (less than one means greater rarity)
local moneyByStepInterval = 0.5      -- initial interval of receiving money per step
local minMoneyByStepInterval = 0.1   -- minimum possible interval between earnings

-- User Interface
local screenGui = Instance.new("ScreenGui")
screenGui.Parent = PlayerGui

local mainFrame = Instance.new("Frame")
mainFrame.AnchorPoint = Vector2.new(0.5, 0.5)
mainFrame.Position = UDim2.new(0.5, 0, 0.5, 0)
mainFrame.Size = UDim2.new(0.6, 0, 0.3, 0)
mainFrame.BackgroundColor3 = Color3.fromRGB(50, 50, 50)
mainFrame.BorderSizePixel = 0
mainFrame.Parent = screenGui

local titleLabel = Instance.new("TextLabel")
titleLabel.Text = "Speed Game"
titleLabel.Font = Enum.Font.GothamBold
titleLabel.TextColor3 = Color3.fromRGB(255, 255, 255)
titleLabel.TextScaled = true
titleLabel.Size = UDim2.new(1, 0, 0.2, 0)
titleLabel.BackgroundTransparency = 1
titleLabel.Parent = mainFrame

local moneyLabel = Instance.new("TextLabel")
moneyLabel.Text = "Money: $"..tostring(money)
moneyLabel.Font = Enum.Font.GothamMedium
moneyLabel.TextColor3 = Color3.fromRGB(255, 255, 255)
moneyLabel.TextScaled = true
moneyLabel.Size = UDim2.new(1, 0, 0.2, 0)
moneyLabel.Position = UDim2.new(0, 0, 0.2, 0)
moneyLabel.BackgroundTransparency = 1
moneyLabel.Parent = mainFrame

local rebirthButton = Instance.new("TextButton")
rebirthButton.Text = "Rebirth ($" .. tostring(rebirthCost) .. ")"
rebirthButton.Font = Enum.Font.GothamBold
rebirthButton.TextColor3 = Color3.fromRGB(255, 255, 255)
rebirthButton.TextScaled = true
rebirthButton.Size = UDim2.new(1, 0, 0.3, 0)
rebirthButton.Position = UDim2.new(0, 0, 0.4, 0)
rebirthButton.BackgroundColor3 = Color3.fromRGB(70, 70, 70)
rebirthButton.Parent = mainFrame

-- Additional upgrade menu
local upgradeMenuButton = Instance.new("TextButton")
upgradeMenuButton.Text = "Upgrades"
upgradeMenuButton.Font = Enum.Font.GothamBold
upgradeMenuButton.TextColor3 = Color3.fromRGB(255, 255, 255)
upgradeMenuButton.TextScaled = true
upgradeMenuButton.Size = UDim2.new(1, 0, 0.3, 0)
upgradeMenuButton.Position = UDim2.new(0, 0, 0.7, 0)
upgradeMenuButton.BackgroundColor3 = Color3.fromRGB(70, 70, 70)
upgradeMenuButton.Parent = mainFrame

local upgradeFrame = Instance.new("Frame")
upgradeFrame.AnchorPoint = Vector2.new(0.5, 0.5)
upgradeFrame.Position = UDim2.new(0.5, 0, 0.5, 0)
upgradeFrame.Size = UDim2.new(0.6, 0, 0.3, 0)
upgradeFrame.BackgroundColor3 = Color3.fromRGB(50, 50, 50)
upgradeFrame.BorderSizePixel = 0
upgradeFrame.Visible = false
upgradeFrame.Parent = screenGui

-- Navigation button "<" to return to the main menu
local backButton = Instance.new("TextButton")
backButton.Text = "<"
backButton.Font = Enum.Font.GothamBold
backButton.TextColor3 = Color3.fromRGB(255, 255, 255)
backButton.TextScaled = true
backButton.Size = UDim2.new(0.1, 0, 0.1, 0)
backButton.Position = UDim2.new(0, 0, 0, 0)
backButton.BackgroundColor3 = Color3.fromRGB(70, 70, 70)
backButton.Parent = upgradeFrame

local payTaxesUpgradeButton = Instance.new("TextButton")
payTaxesUpgradeButton.Text = "Increase Tax Rarity\nPrice: $"..tostring(25)
payTaxesUpgradeButton.Font = Enum.Font.GothamBold
payTaxesUpgradeButton.TextColor3 = Color3.fromRGB(255, 255, 255)
payTaxesUpgradeButton.TextScaled = true
payTaxesUpgradeButton.Size = UDim2.new(1, 0, 0.3, 0)
payTaxesUpgradeButton.Position = UDim2.new(0, 0, 0.1, 0)
payTaxesUpgradeButton.BackgroundColor3 = Color3.fromRGB(70, 70, 70)
payTaxesUpgradeButton.Parent = upgradeFrame

local moneyByStepUpgradeButton = Instance.new("TextButton")
moneyByStepUpgradeButton.Text = "Increase the speed of receiving money\nPrice: $"..tostring(50)
moneyByStepUpgradeButton.Font = Enum.Font.GothamBold
moneyByStepUpgradeButton.TextColor3 = Color3.fromRGB(255, 255, 255)
moneyByStepUpgradeButton.TextScaled = true
moneyByStepUpgradeButton.Size = UDim2.new(1, 0, 0.3, 0)
moneyByStepUpgradeButton.Position = UDim2.new(0, 0, 0.5, 0)
moneyByStepUpgradeButton.BackgroundColor3 = Color3.fromRGB(70, 70, 70)
moneyByStepUpgradeButton.Parent = upgradeFrame

-- Top information panel displaying tax rates and earning speed
local infoPanel = Instance.new("Frame")
infoPanel.AnchorPoint = Vector2.new(0.5, 0)
infoPanel.Position = UDim2.new(0.5, 0, 0, 0)
infoPanel.Size = UDim2.new(1, 0, 0.1, 0)
infoPanel.BackgroundColor3 = Color3.fromRGB(90, 90, 90)
infoPanel.BorderSizePixel = 0
infoPanel.Parent = screenGui

local taxInfoLabel = Instance.new("TextLabel")
taxInfoLabel.Text = "Taxes are collected every "..math.ceil(1/taxRarity).."."
taxInfoLabel.Font = Enum.Font.GothamMedium
taxInfoLabel.TextColor3 = Color3.fromRGB(255, 255, 255)
taxInfoLabel.TextScaled = true
taxInfoLabel.Size = UDim2.new(0.5, 0, 1, 0)
taxInfoLabel.BackgroundTransparency = 1
taxInfoLabel.Parent = infoPanel

local speedInfoLabel = Instance.new("TextLabel")
speedInfoLabel.Text = "Receive money every "..string.format("%.2f", moneyByStepInterval).." seconds."
speedInfoLabel.Font = Enum.Font.GothamMedium
speedInfoLabel.TextColor3 = Color3.fromRGB(255, 255, 255)
speedInfoLabel.TextScaled = true
speedInfoLabel.Size = UDim2.new(0.5, 0, 1, 0)
speedInfoLabel.Position = UDim2.new(0.5, 0, 0, 0)
speedInfoLabel.BackgroundTransparency = 1
speedInfoLabel.Parent = infoPanel

-- Function to receive money for each step
local function getMoneyFromSteps()
    steps += 1
    money += 1*multiplier
    moneyLabel.Text = "Money: $"..tostring(math.floor(money))
end

-- Apply random taxes according to the given frequency
local function applyTax()
    if math.random() <= taxRarity then
        local taxAmount = math.min(money, 4) -- Always pay at least $4, even if you don't have enough
        money = money - taxAmount
        moneyLabel.Text = "Money: $"..tostring(math.floor(money))
        taxInfoLabel.Text = "Paid taxes: -$"..tostring(taxAmount)
    end
end

-- Rebirth function
local function performRebirth()
    if money >= rebirthCost then
        money = money - rebirthCost
        multiplier = multiplier + 1
        rebirthCost = rebirthCost + 50
        steps = 0
        rebirthButton.Text = "Rebirth ($" .. tostring(rebirthCost) .. ")"
        moneyLabel.Text = "Money: $"..tostring(math.floor(money))
    end
end

-- Upgrade: Increase tax rarity
local function buyPayTaxesUpgrade()
    if money >= 25 then
        money = money - 25
        taxRarity = taxRarity / 2   -- Double the tax rarity (reduce how often they occur)
        taxInfoLabel.Text = "Taxes are collected every "..math.ceil(1/taxRarity).."."
        moneyLabel.Text = "Money: $"..tostring(math.floor(money))
    end
end

-- Upgrade: Increase the speed of receiving money
local function buyMoneyByStepUpgrade()
    if money >= 50 and moneyByStepInterval > minMoneyByStepInterval then
        money = money - 50
        moneyByStepInterval = moneyByStepInterval - 0.05 -- Decrease the interval by 0.05
        speedInfoLabel.Text = "Receive money every "..string.format("%.2f", moneyByStepInterval).." seconds."
        moneyLabel.Text = "Money: $"..tostring(math.floor(money))
    end
end

-- Button event handlers
rebirthButton.MouseButton1Click:Connect(performRebirth)
payTaxesUpgradeButton.MouseButton1Click:Connect(buyPayTaxesUpgrade)
moneyByStepUpgradeButton.MouseButton1Click:Connect(buyMoneyByStepUpgrade)

-- Go back to the main menu via the "<" button
backButton.MouseButton1Click:Connect(function()
    upgradeFrame.Visible = false
end)

-- Toggle visibility of the upgrade menu
upgradeMenuButton.MouseButton1Click:Connect(function()
    upgradeFrame.Visible = not upgradeFrame.Visible
end)

-- Regularly check for taxes
task.spawn(function()
    while true do
        task.wait(10) -- Check every 10 seconds
        applyTax()
    end
end)

-- Receive money every N seconds only when you're moving
task.spawn(function()
    while true do
        task.wait(moneyByStepInterval)
        if LocalPlayer.Character and LocalPlayer.Character:FindFirstChildOfClass("Humanoid") then
            local humanoid = LocalPlayer.Character:FindFirstChildOfClass("Humanoid")
            if humanoid.MoveDirection.Magnitude > 0.1 then
                getMoneyFromSteps()
            end
        end
    end
end)

-- Red transparent flashing effect when money is critically low
task.spawn(function()
    while true do
        task.wait(1)
        if money < 0 or money < 2 then
            local flashEffect = Instance.new("Frame")
            flashEffect.BackgroundColor3 = Color3.fromRGB(255, 0, 0)
            flashEffect.BackgroundTransparency = 0.5
            flashEffect.Size = UDim2.new(1, 0, 1, 0)
            flashEffect.Visible = true
            flashEffect.Parent = screenGui
            
            task.wait(0.5)
            flashEffect.Visible = false
            task.wait(0.5)
        end
    end
end)