How to find which team player is in?

I have 2 teams - Blue, and Green team

how do I check which team player is in?

so when I join the game I randomly get put in the blue team, and a GUI will pop that only Blue team members can see.

local player = game:GetService("Players").LocalPlayer

function teamcheck()
 script.Parent.Frame.Visible = true
end

-- if the player is in the blue team then 
-- teamcheck()

Teams - Bright blue Team ; Bright green Team

You could try this code; ultimately you could use "Team Color" or "Player.Team"

local player = game:GetService("Players").LocalPlayer

function teamcheck()
 script.Parent.Frame.Visible = true
end

if player.TeamColour == "Bright blue" -- name of your TeamColor 
then
    teamcheck()
end

local player = game:GetService("Players").LocalPlayer

function teamcheck()
 script.Parent.Frame.Visible = true
end

if player.Team == "Bright blue Team" then
	teamcheck()
end