准备一张小图片，我这里用的一个小苹果
代码：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
img {
position: absolute;
top: 0;
left: 0;
}
</style>
</head>
<body>
<img src="../苹果.png" alt="">
<script>
var img = document.querySelector('img');
document.addEventListener('mousemove', function(e) {
var x = e.pageX;
var y = e.pageY;
img.style.top = y + -16 + 'px';
img.style.left = x + -16 + 'px';
})
</script>
</body>
</html>