A light show is held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)

A light show is held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)

A light show is held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)

A light show is held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)

A light show is held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)

A light show is held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)

A woman takes photo of a light show held at a bell tower in Haikou, south China's Hainan Province, May 1, 2021. Saturday marks the first day of China's five-day May Day holiday. (Xinhua/Pu Xiaoxu)