vue v-show
<!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>
.box {
width: 200px;
height: 200px;
/* 边框 */
border: 1px solid #000;
/* 文字居中 */
text-align: center;
}
</style>
</head>
<body>
<div id="app">
<div class="box" v-show="flag">我是v-show控制的盒子</div>
</div>
<script src="https://cdn.bootcdn.net/ajax/libs/vue/2.7.14/vue.js"></script>
<script>
const app = new Vue({
el: '#app',
data: {
flag: true,
},
})
</script>
</body>
</html>
css 绘制一个矩形
css 语法不熟练