JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap-theme.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
 <div class="row">
    <div class="col-sm-8 center">
    
    <h3>Fill Your Form</h3>
    <div class="row">
    <div class="col-sm-4">
    First Name:
    <input type="text" class="form-control" />
    </div>
    <div class="col-sm-4">
    Middle Name:
    <input type="text" class="form-control" />
    </div>
    <div class="col-sm-4">
    Last Name:
    <input type="text" class="form-control" />
    </div>
    </div>
    <br>
    <div class="row">
    <div class="col-sm-12">
    
 
    <button id="button" class=" btn btn-danger">Generate PDF</button>
    </div>
    </div>

CSS

.center{
	float: none !important;
    margin: 0 auto;
}