<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title>Equal width from top to bottom</title>
<style type="text/css">
.container{
max-width: 960px;/*Set the maximum width to 960px*/
margin: 0 auto;/*Set the inner block element to be horizontally centered*/
}
.header{
height:50px;
background-color: #000000;
}
.main{
height: 600px;
background-color: #6531D0;
}
.footer{
height:50px;
background-color : #000000;
}
</style>
</head>
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
Has your DOM structure been eaten by a dog
No, but the columns should also be displayed on the page! I am a beginner
What do you mean by not showing? Do you have corresponding elements in your body?