修改外层div的位置，浮动元素的位置也会随之改变
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>ff</title> </head> <body> <style type="text/css"> .left_body{ width: 200px; height: 200px; float: left; } #con{ border: 1px solid #0000FF; float:left; } </style> <div> <div></div> <div></div> <div></div> </div> </body> </html>