6.8 避免外边距重叠margin-top: 20px; /* 开启bfc属性 */ /* display: inlin

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    <title>Document</title>
    <style>
        /* div{
            width: 100px;
            height: 100px;
            background-color: red;
        } */
        .cube:first-child{
            width: 100px;
            height: 100px;
            background-color: red;
            margin-bottom: 10px;
        }
        .cube:last-child{
            width: 100px;
            height: 100px;
            background-color: red;
            margin-top: 20px;
            /* 开启bfc属性 */
            /* display: inline-block; */
            /* position: absolute; */
            /* float: left; */
        }
        .container{
            /* 开启bfc属性 */
            overflow: hidden;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="cube"></div>
    </div>

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