老师帮我看看哪里需要优化

来源：2-10 过渡效果实战课（2）

__Promise

2021-05-16 19:20:10

<!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>
        *{
            padding: 0;
            margin: 0;
            list-style: none;
        }
        div{
            width: 800px;
            height: 200px;
            background-color: rgba(255, 99, 71,.1);
            margin: 0 auto;
        }
        div ul{
            overflow: hidden;
        }
        div ul li{
            float: left;
            margin: 10px;
            position: relative;
        }
        div ul li::before{
            content: '';
            display: block;
            width: 180px;
            height: 180px;
            background-size: 100%;
            transition: transform 1s;
        }
        div ul li::after{
            content: '';
            display: block;
            width: 100px;
            height: 100px;
            background-size: 100%;
            position: absolute;
            top: 50%;
            left: 50%;
            margin-top: -50px;
            margin-left: -50px;
            transition: transform 1s;
        }
        div ul .l1::before{
            background-image: url(a_1.png);
        }
        div ul .l2::before{
            background-image: url(a_2.png);
        }
        div ul .l3::before{
            background-image: url(a_3.png);
        }
        div ul .l4::before{
            background-image: url(a_4.png);
        }
        div ul .l1::after{
            background-image: url(icon1.svg);
        }
        div ul .l2::after{
            background-image: url(icon2.svg);
        }
        div ul .l3::after{
            background-image: url(icon3.svg);
        }
        div ul .l4::after{
            background-image: url(icon4.svg);
        }
        div li:hover::before{
            transform: rotate(360deg);
        }
        div li:hover::after{
            transform: scale(1.5);
        }
    </style>
</head>
<body>
    <div>
        <ul>
            <li class="l1"></li>
            <li class="l2"></li>
            <li class="l3"></li>
            <li class="l4"></li>
        </ul>
    </div>
</body>
</html>