01-布局扩展-自适应两栏布局

<!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>
        *{
            margin:0;
            padding:0;
        }
        body,html{
            height:100%;
        }
        .left{
            200px;
            height:80%;
            background:red;
            float:left;
        }
        .right{
            height:100%;
            background:orange;
            /* 触发BFC */
            overflow:hidden;
        }
    </style>
</head>
<body>
    <div class="left"></div>
    <div class="right"></div>
</body>
</html>