• absolute 和 relateive 分别依据什么定位
    • relative 依据自身定位
    • absolute 依据最近一层的 positive / relative 定位
    <!DOCTYPE html>
    <html>
      <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <meta http-equiv="X-UA-Compatible" content="ie=edge" />
        <title>absote relative 定位问题</title>
        <style type="text/css">
          body {
            margin: 20px;
          }
          .relative {
            position: relative;
            width: 400px;
            height: 200px;
            border: 1px solid #ccc;
            top: 20px;
            left: 50px;
          }
          .absolute {
            position: absolute;
            width: 200px;
            height: 100px;
            border: 1px solid blue;
            top: 20px;
            left: 50px;
          }
        </style>
      </head>
      <body>
        <p>absolute 和 relative 定位问题</p>
        <div class="relative">
          <div class="absolute">this is absolute</div>
        </div>
      </body>
    </html>