Teens have been "lying flat" in China and elsewhere for years. Now, the Chinese government is warning it could be the influence of foreign forces that is causing youth to buy into slacker culture. Crispin la valiente/Getty Images " Lying flat" is a meme-y trend among Chinese youth. It's a rebellion against always-on work culture. It's been happening for years, but the Chinese government is now warning it's because of foreign influence. But aren't all teens kind of lazy and rebellious? Isn't that just … teens? It's hard to be a teen. So hard that the mere thought of it makes me, well past my teen years, want to lie down. Understandably, some young people in China have been rebelling against the pressures of modern life for years now — especially the pressures of succeeding in the workforce and a difficult economic environment  — through a meme-y movement called "lying flat," or tang ping  in Chinese. The Chinese government, however, is not loving the meme. And now it's speaking out about it.…