U.S. Democratic Presidential Candidate Hillary Clinton gestures to spectators on the last day of the 2016 U.S. Democratic National Convention at Wells Fargo Center, Philadelphia, Pennsylvania, the United States, on July 28, 2016. Former U.S. Secretary of State Hillary Clinton has formally accepted the U.S. Democratic Party' s nomination for president and pledged more economic opportunities for Americans and "steady leadership". (Xinhua/Li Muzi)