console 命令行工具 X clear
console
<!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>
        .block {
            width: 200px;
            height: 200px;
            color: white;
        }

        .block-1, .block-2 {
            margin: 20px 0;
        }

        .block-1 {
            background-color: steelblue;
        }

        .block-2 {
            background-color: orange;
        }
    </style>
</head>

<body>
    <p>BFC 外边距塌陷</p>
    <div class="block block-1"> </div>
    <div class="block block-2"> </div>

    <p>BFC 外边距塌陷 - 解法</p>
    <div style="overflow:hidden">
        <div  class="block block-1"> </div>
    </div>
    <div>
        <div  class="block block-2"> </div>
    </div>
</body>

</html>