其他---16从中间往两边延伸
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <style> .box{ width:300px; height:100px; border:1px solid red; position: relative; } .box1{ position:absolute; top:0px; left:50%; right:0px; bottom:0px; width:10px; background-color: red; } .box:hover>.box1{ transition: all 3s; left:0px; width:100%; } </style> </head> <body> <div class="box"> <div class="box1"></div> </div> </body> </html>
