Buildings light up blue on the occasion of World Children's Day in the Straits Financial and Business Zone of Fuzhou, southeast China's Fujian Province, 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/Wei Peiquan)

A building lights up blue on the occasion of World Children's Day in the Changfeng commercial district of Taiyuan, north China's Shanxi Province, 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/Cao Yang)

A World Children's Day promotion video is played on an electronic screen in Changchun, northeast China's Jilin Province, 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/Yan Linyun)

Buildings light up blue on the occasion of World Children's Day in the Changfeng commercial district of Taiyuan, north China's Shanxi Province, 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/Cao Yang)

The Central Radio & TV Tower lights up blue on the occasion of World Children's Day in Beijing, capital of China, 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/Chen Zhonghao)

A blue light show is held on the occasion of World Children's Day in Wuhan, central China's Hubei Province, 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/Xiao Yijiu)

A building lights up blue on the occasion of World Children's Day in Weihai, east China's Shandong Province, 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. (Photo by Zhu Chunxiao/Xinhua)

A building lights up with the Chinese characters of "World Children's Day" on the occasion of World Children's Day in southwest China's Chongqing, 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/Huang Wei)

A building lights up blue on the occasion of World Children's Day in Weihai, east China's Shandong Province, 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. (Photo by Zhu Chunxiao/Xinhua)

Buildings light up blue on the occasion of World Children's Day in Shenzhen, south China's Guangdong Province, 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/Mao Siqian)