8.1 粘滞定位/* 粘滞定位 relative + fixed 距离上方50px之前是相对定位 50px之后是固定定位

<!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>
        .container{
            width: 1200px;
            /* 水平居中 */
            margin: 0 auto;
        }
        .container>div{
            width: 1200px;
            height: 700px;
        }
        .container>div:nth-child(odd){
            background-color: white;

        }
        .container>div:nth-child(even){
            background-color: yellow;
        }
        .container>.left,.container>.right{
            width: 150px;
            height: 500px;
            background-color: red;
        }
        .container>.left{
            /* 粘滞定位
            relative + fixed
            距离上方50px之前是相对定位 50px之后是固定定位 */
            position: sticky;
            top: 50px;
        }
        .container>.right{
            float: right;
            position: sticky;
            top: 50px;
        }
    </style>
</head>
<body>
    <div class="container">
        <div></div>
        <div></div>
        <!-- 优先加载右侧后左侧 -->
        <aside class="right"></aside>
        <aside class="left"></aside>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
        <div></div>
    </div>
</body>
</html>