<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> <link rel="stylesheet" href="bootstrap/css/bootstrap.css"> <link rel="stylesheet" href="bootstrap/css/bootstrap-theme.css"> <script src="bootstrap/js/jquery-3.2.1.js"></script> <script src="bootstrap/js/bootstrap.js"></script> <style> .top { border: 1px solid red; overflow: hidden; } .pull-left { width: 200px; height: 200px; background-color:blue; } .pull-right { width: 200px; height: 200px; background-color: green; } </style> </head> <body style="background: white;"> <!--浮动的使用--> <div class="container"> <div class="top"> <div class="pull-left"></div> <div class="pull-right"></div> </div> </div> </body> </html>