Run Example

Edit This Code:
<!DOCTYPE html>
<html lang="en">
<head>
  <title>Bootstrap Example</title>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
  <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script>
</head>
<body>

 <div class="container-fluid">
  <h1>Single Column</h1>
  <p>Here is a most basic example using grid system which gives a single column:</p>
  <div class="row">
    <!-- <div class="col-sm-4" style="background-color:lavender;">.col-sm-4</div> -->
    <div class="col-md-12" style="background-color:lightblue;"> col-md-12 </div>
  </div>
 </div>

</body>
</html>
Result: