console 命令行工具 X clear
console
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            box-sizing: border-box;
            border: 1px solid red;
        }
        
        .parent1,
        .parent2 {
            width: 100%;
            height: 120px;
            margin: 10px;
            position: relative;
        }
        
        .parent1 .box-left {
            width: auto;
            height: 100px;
            background-color: blue;
            margin: 10px;
            margin-right: 120px;
        }
        
        .parent1 .box-right {
            position: absolute;
            right: 0px;
            top: 0px;
            width: 100px;
            height: 100px;
            background-color: yellow;
            margin: 10px;
        }
        
        .parent2 .box-left {
            width: 100px;
            height: 100px;
            float: left;
            background-color: yellow;
            margin: 10px;
        }
        
        .parent2 .box-right {
            width: auto;
            height: 100px;
            background-color: blue;
            margin: 10px;
            margin-left: 120px;
        }
    </style>
</head>

<body>
    <div class="parent1">
        <div class="box-left"></div>
        <div class="box-right"></div>
    </div>
    <div class="parent2">
        <div class="box-left"></div>
        <div class="box-right"></div>
    </div>


</body>

</html>