通过使用.col-md-push- 和.col-md-pull-类就可以很容易的改变列（column）的排序。
    image.png

    1. <!DOCTYPE html>
    2. <html lang="en">
    4. <head>
    5.   <meta charset="UTF-8">
    6.   <meta http-equiv="X-UA-Compatible" content="IE=edge">
    7.   <meta name="viewport" content="width=device-width, initial-scale=1.0">
    8.   <title>Document</title>
    9.   <link rel="stylesheet" href="bootStrap/css/bootstrap.min.css">
    10. </head>
    12. <body>
    13.   <div class="container">
    14.     <div class="row">
    15.       <div class="col-md-6 col-md-push-6">2</div>
    16.       <div class="col-md-6 col-md-pull-6">1</div>
    17.     </div>
    18.   </div>
    19. </body>
    21. </html>

    image.png