<link href="//netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css"> <script src="//netdna.bootstrapcdn.com/bootstrap/3.0.0/js/bootstrap.min.js"></script> <script src="//code.jquery.com/jquery-1.11.1.min.js"></script> <!------ Include the above in your HEAD tag ----------> <div class="container"> <div class="row"> <div class="center span2 well"> <legend>Please Sign In</legend> <div class="alert alert-error"> <a class="close" data-dismiss="alert" href="#">×</a>Incorrect Username or Password! </div> <form method="POST" action="" accept-charset="UTF-8"> <input type="text" id="username" class="span4" name="username" placeholder="Username" /> <input type="password" id="password" class="span4" name="password" placeholder="Password" /> <label class="checkbox"> <input type="checkbox" name="remember" value="1" /> Remember Me </label> <button type="submit" name="submit" class="btn btn-primary btn-block">Sign in</button> </form> </div> </div> </div>

.center {float: none; margin-left: auto; margin-right: auto;}