响应式布局
参考网站：http://alistapart.com/article/responsive-web-design
peter老师的书：book.haoduoshipin.com/go-responsive
以下为两个实例
（一）三个盒子的media query,用了个clear:none;覆盖上级clear:both;
I was born fin a small village not far from the sea.
Peach flowers were the most beautiful thing in my eyes,until several years later
I found girls were even more attractive.