背景颜色css不适用

Question

 <div id="popup-data"><h3 class="display-title">Selected Items</h3>

        <div class="taxonomy-fancybox-item-wrapper">
<div class="parent-li"><h3>
<a href="/ajax/remove-term/1" class="delete-parent-link">X</a> Test 1A:
</h3>
</div>
<div class="child-li">Test 2A <a href="/ajax/remove-term/2/1" class="delete-child-link">X</a>
</div>
<div class="child-li">Test 3A <a href="/ajax/remove-term/3/1" class="delete-child-link">X</a>
</div>
</div>
<div class="taxonomy-fancybox-item-wrapper">
<div class="parent-li"><h3><a href="/ajax/remove-term/5" class="delete-parent-link">X</a> Test 1B:</h3></div><div class="child-li">Test 2B <a href="/ajax/remove-term/6/5" class="delete-child-link">X</a></div></div><div class="taxonomy-fancybox-item-wrapper"><div class="parent-li"><h3><a href="/ajax/remove-term/9" class="delete-parent-link">X</a> Test 1C:</h3></div><div class="child-li">Test 2C <a href="/ajax/remove-term/10/9" class="delete-child-link">X</a></div><div class="child-li">Test 3C <a href="/ajax/remove-term/11/9" class="delete-child-link">X</a></div></div><div class="taxonomy-fancybox-item-wrapper"><div class="parent-li"><h3><a href="/ajax/remove-term/13" class="delete-parent-link">X</a> Test 1D:</h3></div><div class="child-li">Test 2D <a href="/ajax/remove-term/14/13" class="delete-child-link">X</a></div><div class="child-li">Test 3D <a href="/ajax/remove-term/15/13" class="delete-child-link">X</a></div><div class="child-li">Test 4D <a href="/ajax/remove-term/16/13" class="delete-child-link">X</a></div><div class="child-li">Test 5D <a href="/ajax/remove-term/17/13" class="delete-child-link">X</a></div></div>  
    </div>

为弹出数据添加的样式是（在css文件中）

#popup-data {
  background-color:aliceblue;
}

看到的是背景色被错误添加，如下所示 什么是不正确的HTML，我甚至检查但没有找到任何不完整的div