bootstrap 3 offset

col-sm-offset-2

 <form action="/action_page.php">
  <div class="form-group">
    <label for="email">Email address:</label>
    <input type="email" class="form-control" id="email">
  </div>
  <div class="form-group">
    <label for="pwd">Password:</label>
    <input type="password" class="form-control" id="pwd">
  </div>
  <div class="checkbox">
    <label><input type="checkbox"> Remember me</label>
  </div>
  <button type="submit" class="btn btn-default">Submit</button>

 </form> 

 <div class="row">
  <div class="col-sm-4">.col-sm-4</div>
  <div class="col-sm-4">.col-sm-4</div>
  <div class="col-sm-4">.col-sm-4</div>
</div> 

--------------------------------------------------------------------------------------
Bootstrap Container Width			 					| Size        | Class Prefix
--------------------------------------------------------------------------------------
Extra small devices Phones (less than 768px)  			| None (auto) | .col-xs-
Small devices Tablets (greater than equals 768px) 		| 750px       | .col-sm-
Medium devices Desktops (greater than equals 992px)     | 970px       | .col-md-
Large devices Desktops (greater than equals 1200px)     | 1170px      | .col-lg-