A building lights up blue on the occasion of World Children's Day in Yinchuan, northwest China's Ningxia Hui Autonomous Region, Nov. 20, 2020. Buildings and iconic monuments in some Chinese cities went blue on Friday to celebrate World Children's Day. World Children's Day is celebrated on November 20 each year to promote international togetherness, awareness among children worldwide, and improving children's welfare. (Xinhua/Wang Peng)