<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8>
<style type="text/css">
* {
margin: 0;
padding: 0;
}
.advert {
width: 300px;
height: 200px;
background-color: black;
position: fixed;
right: 0;
bottom: 0;
}
.advert:first-line {
color: white;
}
.x {
position: absolute;
right: 0;
}
</style>
</head>
<body>
<section class="advert">
广告文案
<button class="x">x</button>
</section>
<script>
document.querySelector('button').onclick = function() {
this.parentNode.style.display = 'none'
}
</script>
</body>
</html>