           image = new Image
           image.src = val
 
-    @_cubes[setsKeys[0]].el.style.marginLeft = '0'
-    @_cubes[setsKeys[setsKeys.length - 1]].el.style.marginRight = '0'
+    @cubes[setsKeys[0]].el.style.marginLeft = '0'
+    @cubes[setsKeys[setsKeys.length - 1]].el.style.marginRight = '0'
 
     @el.classList.add @className
     @el.style.height = @size + 'px'

      console?.warn "#{ baseName }: CSS transforms are not supported in this browser."
      return

    @_cubes = {}
    @[option] = @options[option] ? defaults[option] for option, value of defaults
    @fontSize += 'px' if typeof @fontSize is 'number'


    i = z = 0
    midPoint = setsLength / 2 + 1
    for key, set of @sets
      cube = @cubes[key] = @_createCube key
      if ++i < midPoint
        z++
      else
