```css <form action="" role="form" class="form-horizontal"> <div class="form-group"> <label for="" class="col-xs-2">用户名</label> <div class="col-xs-10"> <input type="text" class="form-control "> </div> </div> <div class="form-group"> <label for="" class="col-xs-2">密码</label> <div class="col-xs-10"> <input type="text" class="form-control"> </div> </div> <div class="form-group"> <div class="checkbox col-xs-10 col-xs-offset-2"> <label for=""> <input type="checkbox">记住密码 </label> </div> </div> <div class="form-group"> <div class="col-xs-10 col-xs-offset-2"> <button type="submit" class="btn btn-default">提交</button> </div> </div> </form> ``` ``` form class="form-horizontal" div class="form-group" ```