<!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>
width: 300px;
height: 300px;
background: red;
margin: 50px;
border: 1px solid gray;
}
width: 500px;
height: 500px;
border: 1px solid
background: green;
position: absolute;
top: 0;
left: 300px;
background-repeat: no-repeat;
}
</style>
</head>
<body>
<div id="left" style="background: url(./img/5a445ba0N2b96e844.jpg) 0 / 100% 100%;"></div>
<div id="right" style="background: url(./img/5a445ba0N2b96e844.jpg) center; background-size: 200% 200%;"></div>
<script>
function $(str){
return document.querySelector(str)
}
window .onload =function(){
let l =$('#left').offsetLeft +$('#left').offsetWidth
let t =$('#left').offsetTop
$('#right').style.left =l +'px'
$('#right').style.top =t +'px'
$('#left').onmouseenter =() =>{
$('#right').style.display ='block'
}
$('#left').onmouseleave =() =>{
$('#right').style.display ='none'
}
$('#left').onmousemove =(e)=>{
let x = e.pageX -$('#left').offsetLeft
let y = e.pageY -$('#left').offsetTop
x=x/$('#left').offsetWidth
y=y/$('#left').offsetHeight
x=(x*100).toFixed(4)+"%"
y=(y*100).toFixed(4)+"%"
$("#right").style['background-position-x']=x
$("#right").style['background-position-y']=y
}
}
</script>
</body>
</html>
