Challenge with Serving Static files

Hello ,
This is the snippet of the code

defmodule PlugEx.Router do
	use Plug.Router
	use Plug.Debugger
	plug(Plug.Logger, log: :debug)
	plug :match
	plug :dispatch
	plug Plug.Static, at: "/", from: :server, only: ~w(js css images robots.txt)

	get "/" do
		send_resp(conn, 200, "Hello There!")
	end

	get "/about/:user_name" do
		send_resp(conn, 200, "Hello, #{user_name}")
	end

	get "/home" do
		conn = put_resp_content_type(conn, "text/html")
		send_file(conn, 200, "priv/index.html")
	end


	match _, do: send_resp(conn, 404, "404 error not found!")
end