<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<link rel="stylesheet" href="bootstrap/css/bootstrap.min.css">
<script src="bootstrap/js/jquery-3.4.1.js"></script>
<script src="bootstrap/js/bootstrap.js"></script>
<style>
div[class^='col-md'] {
border: 1px solid #ccc;
}
</style>
</head>
<body>
<div class="container">
<h2>默认</h2>
<div class="row">
<div class="col-md-2">col-md-2</div>
<div class="col-md-3">col-md-3</div>
<div class="col-md-4">col-md-4</div>
</div>
<h2>偏移</h2>
<div class="row">
<div class="col-md-2 col-md-offset-1">col-md-2</div>
<div class="col-md-3">col-md-3</div>
<div class="col-md-4">col-md-4</div>
<div class="col-md-2 col-md-offset-2">col-md-2</div>
<div class="col-md-3">col-md-3</div>
<div class="col-md-4">col-md-4</div>
</div>
<h2>列嵌套</h2>
<div class="row">
<div class="col-md-2">col-md-2</div>
<div class="col-md-3">col-md-3</div>
<div class="col-md-4">
<div class="row">
<div class="col-md-4">嵌套列</div>
<div class="col-md-4">嵌套列</div>
<div class="col-md-4">嵌套列</div>
<div class="col-md-4">嵌套列</div>
</div>
</div>
</div>
</div>
</body>
</html>
