How are the following arrows displayed without an image?
I have a mockup here

http://jsfiddle.net/yug3Q/1/

If you click on a date you get forward and back arrows.  These do not appear to be images I would like to know how they are rendered.
How are the following arrows displayed without an image?
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I have a mockup here

http://jsfiddle.net/yug3Q/1/

If you click on a date you get forward and back arrows.  These do not appear to be images I would like to know how they are rendered.