Why is the roof of Shuangjiang County blue?

Good-looking. Blue represents the blue sky, the same color as the sky, and the blue roof looks better. Shuangjiang County, full name of lahu-va-blang-dai autonomous county of shuangjiang, belongs to lincang. The county covers an area of 2 165.03 square kilometers and has jurisdiction over 4 townships, 2 towns, 72 villages, 3 communities, Mengku Overseas Chinese Management Zone and Shuangjiang Farm Management Committee.