个人理解无界原理

<!DOCTYPE html>

<html lang="en">

<head>

<meta charset="UTF-8">

<meta name="viewport" content="width=device-width, initial-scale=1.0">

<title>Document</title>

</head>

<style>

#acb{

color: green;

}

.aaa{

color: red;

}

</style>

<body>

<div id="acb">22</div>

<div id="shadown">

<!-- <wujie-app></wujie-app> -->

</div>

</body>

<script>

const host = document.querySelector("#shadown");

const shadow = host.attachShadow({ mode: "open" });

const aa = document.createElement("wujie-app")

shadow.appendChild(aa)

class MyCustomElement extends HTMLElement {

constructor() {

super();

//const s = document.getElementById("tem")

const ht = document.createElement("html")

const bo = document.createElement('body')

const div = document.createElement("div")

div.innerHTML = 111112222

div.id='acb'

bo.appendChild(div)

ht.appendChild(bo)

this.appendChild(ht)

// 在这里可以进行元素的初始化操作，比如添加内容、样式等

}

}

customElements.define('wujie-app', MyCustomElement);

</script>

</html>