What are various boxes in international trade?

The various boxes in International trade are:
Green box: supports considered not to distort trade and therefore permitted with no limits, no restrictions are there in this category.

Blue box: permitted supports linked to production, but subject to production limits, and therefore minimally trade-distorting. Production caps are placed to control the level of production.

Amber box: supports considered to distort trade and therefore subject to reduction commitments.