colorpicker demo won't work locally if downloaded

colorpicker demo won't work locally if downloaded

I downloaded the "colorpicker" demo from http://jqueryui.com/demos/slider/colorpicker.html
so I could experiment with it.
At first it showed no bars. I determined that was because the css file
imported files local to the jquery site.
I located and downloaded ui.theme.css and ui.base.css.
Now there were bars, but no slider handle, and no colors to the left
of the handle.
Can anyone tell me what files I need to run the colorpicker demo
locally?
And, wouldn't it be a good practice to include all necessary files
with demos so that they would work properly when downloaded?
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