1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 <style> 7 body{ 8 margin: 0; 9 } 10 11 .model{ 12 position: fixed; 13 top: 0; 14 bottom: 0; 15 left: 0; 16 right: 0; 17 background:rgba(0,0,0,.5); 18 z-index: 2; 19 } 20 21 .content{ 22 height: 281px; 23 width: 400px; 24 background-color: white; 25 position: fixed; 26 top: 50%; 27 left: 50%; 28 z-index: 3; 29 margin-left: -200px; 30 margin-top: -200px; 31 } 32 .content_1{ 33 z-index: 4; 34 position: fixed; 35 top: 50%; 36 left: 50%; 37 margin-left: -200px; 38 margin-top: -200px; 39 } 40 </style> 41 </head> 42 <body> 43 <div style="height: 2000px;background-color: darkgrey"> 44 <h1>你好明天</h1><h1>你好明天</h1><h1>你好明天</h1><h1>你好明天</h1><h1>你好明天</h1><h1>你好明天</h1> 45 46 </div> 47 <div class="model"></div> 48 <div class="content"></div> 49 <div class="content_1"> 50 <img src="20.gif"> 51 </div> 52 53 </body> 54 </html>