 
   destroy: ->
     $(document).off('keyup')
+    @container.remove()
 
   whenIdle: (callback) =>
     @queue.push(callback)

    })

    # make container
    container = $('<div id=container></div>').css({
        position: 'absolute'
        top: (@here.height - @above.height + 71) / 2
        left: (@here.width - @above.width + 71) / 2
    })
    frame.append(container)

    # make invisible grid on which the pawn moves
    grid = $('<div id=grid></div>').css({

            context.lineWidth = 2
            context.stroke()
      @floors[z] = floor
      @container.append(floor)
      floor.css({
          position: 'absolute'
      })
