Hello teacher, your code in Chapters 2 and 3 cannot be executed in my environment. My environment is: phpstrom2018.3 chorme jquery3.3.1.js, the code is as follows:
-------------------------- -------------------------------------------------- -----
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset= "UTF-8">
<title>Selector - General Filter</title>
<script src="../js/jquery-3.3.1.js"> </script>
<script>
$(function () {
#ccc");
//2. Class selector
$(".red").css("color","red");
//3. ID selector
$("#active").css("backgroup-color","#ff0");
})
</script>
</head>
<body>
<h2>1. General filter</h2>
<ul>
li>PHP中文网02</li>
’ ’ ’ outbeing out out's having dar's to ward over ward's ‐ ‐ ‐ ‐ ‐ < /li>
; <li class="red">PHP Chinese Network 05</li>
#
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
知识，成就梦想！