使用定位，制作弹出框界面：
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <!-- reset.css文件内容参考：https://www.cnblogs.com/lanshanxiao/p/12663192.html --> <link rel="stylesheet" href="./reset.css"> <style> img{ width:500px; height:500px; } /* 遮罩层，半透明 */ .container .main{ position:fixed; width:100%; height:100%; top:0; left:0; background-color: rgba(0,0,0,.5); } /* 设置弹出层样式 */ .container .main .login{ position:absolute; left:0; right:0; top:0; bottom:0; margin:auto; width:500px; height:500px; background-color: #fff; border-radius: 5px; padding:20px; } /* 设置关闭样式 */ .container .main .login .close{ width:20px; height:20px; box-sizing: border-box; border-radius: 50%; background-color: rgba(255,255,255,.5); color:#999; text-align: center; line-height: 20px; font-size:18px; position:absolute; top:0; right:0; } </style> </head> <body> <div class="container"> <img src="http://i-1-33app.qqxzb-img.com/2019/11/15/6fd81ae2-4e85-43da-b5bd-e810cd54c82c.jpg?imageView2/2/q/85" alt=""> <div class="main"> <div class="login"> Lorem ipsum dolor sit amet consectetur adipisicing elit. Debitis consectetur laboriosam maiores sequi deleniti nihil cumque repellendus ea, harum a, vero voluptatum dicta dolorem blanditiis, accusamus saepe fugit cum vel? <div class="close"> x </div> </div> </div> </div> </body> </html>
效果展示：
