title: Why icon can not be dispalyed corrent in css defination
body: <p>In my project, i want to use a icon, here is html code:</p>
  
  <pre><code> &lt;span class="item-title-icon"&gt;&lt;/span&gt;
  </code></pre>
  
  <p>and here is defination of icon:</p>
  
  <pre><code>.item-title-icon
    position: relative
    left: .06rem
    top: .06rem
    display: inline-block
    width: .36rem
    height: .36rem
    background-size: .4rem 3rem
    background: url(http://s.qunarzz.com/piao/image/touch/sight/detail.png) 0 -.45rem no-repeat
    margin-right: .1rem
  </code></pre>
  
  <p>unlucky, It display wrong, the icon can not display correct, only part of it displays. And it seems nothing wrong, who can help me ?</p>