点击元素，只有它的背景变色

【要求】：点击 li 元素，当且只有它的背景变为红色。

【实现】：

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>

    <style>
        .red {
            background: red;
        }
    </style>
</head>

<body>
    
    <ul id="list">
        <li>12345</li>
        <li>12345</li>
        <li>12345</li>
        <li>12345</li>
        <li>12345</li>
    </ul>

    <script>
        var oList = document.getElementById('list');
        
        oList.addEventListener('click', function(e) {
            var target = e.target || e.srcElement;
        
            var oLi = oList.children;
        
            for (var i=0; i< oLi.length; i++) {
                oLi[i].className = '';
            }
        
            target.className = 'red';
        }, false);
    </script>
</body>
</html>

Scoop It and Enjoy the Ride！