add mono css framework, add some boiler plate, get started on responsive design fixes

lib/layouts/page_layout.ex

@@ -0,0 +1,10 @@
+defmodule Llmex.PageLayout do
+  use Tableau.Layout, layout: Llmex.RootLayout
+  use Phoenix.Component
+
+  def template(assigns) do
+    ~H"""
+    <%= {:safe, render(@inner_content)} %>
+    """
+  end
+end