Bootstrap实现嵌套，网页不显示


<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width = device -width"/>
    <title>Title</title>
    <link href="../css/bootstrap.css" rel="stylesheet">

    <style>
        .col-6 {
            width: 600px;
            height: 300px;
            border: solid red 1px;
        }
        .col-3{
            width: 600px;
            height:300px;
            border: solid red 1px;
        }
        .rows-6{

            height: 300px;
            border: solid red 1px;
        }
        .col{
            width: 600px;
            height: 300px;
            border: solid red 1px;
        }
        .row{
            width: 600px;
            border: solid red 1px;
        }
    </style>
</head>
<body>
<div class="container">

    <div class="row">
        <div class="col-6"></div>
        <div class="col-6"> <div class="row-6"></div> <div class="row-6"></div> </div>
    </div>

    <div class="row">
        <div class="col-6"></div>
        <div class="col-3"></div>
        <div class="col-3"></div>
    </div>


</div>
</body>
</html>

img


想要实现这个样式，貌似嵌套实现不出来，

img

哈喽，代码如下：

 
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width = device -width"/>
    <title>Title</title>
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css" integrity="sha384-HSMxcRTRxnN+Bdg0JdbxYKrThecOKuH5zCYotlSAcp1+c8xmyTe9GYg1l9a69psu" crossorigin="anonymous">

    <!-- 可选的 Bootstrap 主题文件（一般不用引入） -->
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap-theme.min.css" integrity="sha384-6pzBo3FDv/PJ8r2KRkGHifhEocL+1X2rVCTTkUfGk7/0pbek5mMa1upzvWbrUbOZ" crossorigin="anonymous">

    <!-- 最新的 Bootstrap 核心 JavaScript 文件 -->
    <script src="https://stackpath.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js" integrity="sha384-aJ21OjlMXNL5UyIl/XNwTMqvzeRMZH2w8c5cRVpzpU8Y5bApTppSuUkhZXN0VxHd" crossorigin="anonymous"></script>
    <style>
        .height400{
          height:400px;
        }
        .height100{
          height:100px;
        }
        .height200{
          height:200px;
        }
        .border{
            border: solid red 1px;
        }
    </style>
</head>
<body>
<div class="container">
  <div class="row">
    <div class="col-md-6 border height400">.col-md-6</div>
    <div class="col-md-6">
      <div class="row">
        <div class="col-md-12 border height200">.col-md-6 .col-md-12</div>
      </div>
      <div class="row">
        <div class="col-md-6 border height200">.col-md-6 .col-md-6</div>
        <div class="col-md-6">
          <div class="row">
            <div class="col-md-12 border height100">.col-md-6 .col-md-6 .col-md-12</div>
          </div>
          <div class="row">
            <div class="col-md-12 border height100">.col-md-6 .col-md-6 .col-md-12</div>
          </div>
        </div>
      </div>
    </div>
  </div>
  <div class="row">
    <div class="col-md-6 border height400">.col-md-6</div>
    <div class="col-md-3">
      <div class="row"> <div class="col-md-12 border height200">.col-md-3 .col-md-12</div></div>
      <div class="row"> <div class="col-md-12 border height200">.col-md-3 .col-md-12</div></div>
    </div>
    <div class="col-md-3 border height400">.col-md-3</div>
  </div>
</div>
</body>
</html>