docs: def website(app=None, mode='home', subcontext='UserGuide'):
      """
      Returns the website location for projex software.
      
      :param      app  | <str> || None
                  mode | <str> (home, docs, blog, dev)
      
      :return     <str>
      """
      base_url = WEBSITES.get(mode, '')
  
      if app and base_url:
          opts = {'app': app, 'base_url': base_url}
          base_url = SUBCONTEXT_MAP.get((mode, subcontext), base_url)
          base_url %= opts
  
      return base_url