您可以尝试运行以下代码来构建响应式网格视图：
<!DOCTYPE html>
<html>
<head>
<meta name = "viewport" content = "width = device-width, initial-scale = 1.0">
<style>
* {
box-sizing: border-box;
}
.header {
border: 1px solid black;
padding: 10px;
}
.leftmenu {
width: 30%;
float: left;
padding: 10px;
border: 1px solid black;
}
.content {
width: 70%;
float: left;
padding: 10px;
border: 2px dotted black;
}
</style>
</head>
<body>
<div class = "header">
<h1>Header</h1>
</div>
<div class = "leftmenu">
<ul>
<li>Menu One</li>
<li>Menu Two</li>
<li>Menu Three</li>
<li>Menu Four</li>
<li>Menu Five</li>
<li>Menu Six</li>
<li>Menu Seven</li>
<li>Menu Eight</li>
<li>Menu Nine</li>
<li>Menu Ten</li>
</ul>
</div>
<div class = "content">
<h1>Demo</h1>
<p>This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text. This is demo text. This is demo text.
This is demo text.
</p>
</div>
</body>
</html>