let和var的区别
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style>
.item {
float: left;
width: 100px;
height: 100px;
margin: 0 10px ;
border: 1px solid purple;
}
</style>
</head>
<body>
<div class="container">
<h2>点击切换颜色</h2>
<div class="item"></div>
<div class="item"></div>
<div class="item"></div>
</div>
<script>
let items = document.getElementsByClassName('item');
for(let i = 0; i < items.length; i++) {
items[i].onclick = function() {
items[i].style.background = 'pink'
}
}
</script>
</body>
</html>