从自举转盘中移除右侧和左侧暗区

Question

我在jsfiddle中有一个引导旋转木马here，我试图看看我是否可以在左侧和右侧设置控件/箭头的样式，这样它们在有和没有悬停的情况下都不显示更暗的区域在箭头/侧面区域。我只是希望箭头突出显示它们悬停在上面。

这是我的基本轮播代码

.item img {width: 100%; height: auto}

<div id="carousel-example-generic" class="carousel slide" data-ride="carousel">
  <!-- Indicators -->
  <ol class="carousel-indicators">
    <li data-target="#carousel-example-generic" data-slide-to="0" class="active"></li>
    <li data-target="#carousel-example-generic" data-slide-to="1"></li>
    <li data-target="#carousel-example-generic" data-slide-to="2"></li>
  </ol>

  <!-- Wrapper for slides -->
  <div class="carousel-inner" role="listbox">
    <div class="item active">
      <img src="http://placehold.it/450x350" alt="Slide 1">
      <div class="carousel-caption">
        Caption Slide 1
      </div>
    </div>
    <div class="item">
      <img src="http://placehold.it/450x350" alt="Slide 2">
      <div class="carousel-caption">
        Caption Slide 2
      </div>
    </div>
    <div class="item">
      <img src="http://placehold.it/450x350" alt="Slide 3">
      <div class="carousel-caption">
        Caption Slide 3
      </div>
    </div>        
  </div>

  <!-- Controls -->
  <a class="left carousel-control" href="#carousel-example-generic" role="button" data-slide="prev">
    <span class="glyphicon glyphicon-chevron-left" aria-hidden="true"></span>
    <span class="sr-only">Previous</span>
  </a>
  <a class="right carousel-control" href="#carousel-example-generic" role="button" data-slide="next">
    <span class="glyphicon glyphicon-chevron-right" aria-hidden="true"></span>
    <span class="sr-only">Next</span>
  </a>
</div>