Mandala

In tibetan Buddhism the Kalachakra Mandala is a cosmographic representation of the inner, outer, and alternative dimensions of reality. 

The Body Mandala is surrounded by crescent-shaped areas, which are the offering grounds. 

Next follow circles which represent the elements: earth (yellow), water (white), fire (pink/red), wind (gray/black) and space (green). 
The outermost circle is the "Great Protective Circle", "Mountain of Flames" or "Circle of Wisdom" which represents the wisdom element. 

The differently colored areas represent the five Wisdoms of the Buddha in the form of a rainbow.

Picture taken from a Kalachakra Mandala tanka in Kathmandu....
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