css布局之左侧宽度固定，右侧宽度自适应

方案一：利用padding-left预留空间，左侧脱标，右侧宽度相当于父元素的100%

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>左侧宽度固定，右侧宽度自适应</title>
    <style>
        .container{
            padding-left: 300px;
             100%;
            height: 500px;
            background-color: cadetblue;
            position: relative;
        }
        .left{
            position: absolute;
            left: 0;
            top: 0;
             300px;
            height: 500px;
            background-color: brown;
        }
        .right{
            height: 500px;
             100%;
            background-color: aqua;
        }
    </style>
</head>
<body>
<div class="container">
   <div class="left">left</div>
   <div class="right">
       right
       right
       right
       right
       right
   </div>
</div>
</body>
</html>

方案二：左侧设置浮动，右侧不指定宽度

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .left{
            float: left;
             500px;
            height: 500px;
            background-color: cadetblue;
        }
        .right{
            height: 500px;
            background-color: brown;
        }
    </style>
</head>
<body>
<div class="left">left</div>
<div class="right">right</div>
</body>
</html>