css - Bootstrap 下拉菜单后显示额外的箭头

Question

<div>
                                    <div class="dropdown" style="float:right">
                                          <button class="btn btn-primary dropdown-toggle" type="button" data-toggle="dropdown">
                                            Admin<span class="caret"></span>
                                          </button>
                                        <ul class="dropdown-menu">
                                            <li><a href="#">HTML</a></li>
                                            <li><a href="#">CSS</a></li>
                                            <li><a href="#">JavaScript</a></li>
                                        </ul>
                                    </div>
                                </div>

这是代码..所以我怎样才能删除附加到按钮的额外箭头，如图所示？

CSS如下，写在style.css中:

.dropdown {
    position: relative;
    min-width: 130px;
    /*padding-right: 34px;*/
    height: 34px;
    background: #fff;
    -moz-border-radius: 4px;
    -webkit-border-radius: 4px;
    border-radius: 4px;
    border: 1px solid rgba(0,0,0,0.15);
    border-bottom: 1px solid rgba(0,0,0,0.3);
    -moz-box-shadow: 0 1px 1px rgba(0,0,0,0.15);
    -webkit-box-shadow: 0 1px 1px rgba(0,0,0,0.15);
    box-shadow: 0 1px 1px rgba(0,0,0,0.15);
    margin-top: 12px;
}

Answer 1

评论后编辑

@import url('http://getbootstrap.com/dist/css/bootstrap.css');

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/2.1.0/bootstrap.min.js"></script>
<div class="container">
  <h2>Dropdowns</h2>                                        
  <div class="dropdown">
    <button class="btn btn-primary dropdown-toggle" type="button" id="menu1" data-toggle="dropdown">Drop Down
    <span class="caret"></span></button>
    <ul class="dropdown-menu" role="menu" aria-labelledby="menu1">
      <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Example</a></li>
      <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Example2</a></li>
      <li role="presentation"><a role="menuitem" tabindex="-1" href="#">Example3</a></li>
      <li role="presentation" class="divider"></li>
      <li role="presentation"><a role="menuitem" tabindex="-1" href="#">About Us</a></li>
    </ul>
  </div>
</div>