宽度固定，上栏高度固定，下栏高度自适应。
1.flex布局
<!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> * { padding: 0; margin: 0; } html, body { height: 100%; } .content { display: flex; flex-direction: column; width: 100%; height: 100%; } .top { width: 100%; height: 200px; background-color: blue; } .bottom { width: 100%; flex: 1; background-color: red; } </style> </head> <body> <div class="content"> <div class="top"></div> <div class="bottom"></div> </div> </body> </html>
2.绝对定位布局
<!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> * { padding: 0; margin: 0; } html, body { height: 100%; } .content { position: relative; width: 100%; height: 100%; } .top { position: absolute; width: 100%; top: 0; left: 0; height: 200px; background-color: blue; } .bottom { position: absolute; top: 100px; left: 0; width: 100%; height: 100%; flex: 1; background-color: red; } </style> </head> <body> <div class="content"> <div class="top"></div> <div class="bottom"></div> </div> </body> </html>