A股大跳水，指数午后大幅回落，创业板指翻绿，此前一度涨近3%，沪指午后单边回落跌近1.4%

Group 1 - The index experienced a significant decline in the afternoon, with the ChiNext index turning negative after previously rising nearly 3% [1] - The Shanghai Composite Index fell nearly 1.4% in the afternoon session [1]