<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>Test</title><style type="text/css">.1{background-color:#F00;width:100px;height:100px;float:left}.2{background-color:#0F0;width:200px;height:200px;float:left}.3{background-color:#0F0;width:50px;height:50px;float:left;clear:left}</style></head><body><div class="1"></div><div class="2"></div><div class="3"></div></body></html>
Of course the box will not be displayed if you don’t set the border... ............Depressed There are still questions. In-site message
I am stumped by the poster’s question!
Of course the frame won’t be displayed if you don’t set the border.......................Depressing There are still problems. In-site message
Start I thought it was very simple, but after trying it myself, I realized that it was because the value of class cannot be a number. I had never paid attention to it before, so I learned.
Quote from the 1st floor’s reply:
Of course you won’t display the frame if you don’t set the border............. Depressing There are still questions. In-site messages
I thought it was very simple at first, but after trying it myself, I realized that it is because the value of class cannot be a number. I haven't paid attention to it before. Study.
Oh, this naming convention requires that you cannot do this. . . . . . .
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
