side 图片轮播，让图片居中

<div class="mui-slider-group mui-fullscreen mui-slider-loop">
<!--支持循环的，节点-->
<div class="mui-slider-item mui-fullscreen mui-slider-item-duplicate">
<a href="#"><img src="images/04/1.jpg"></a>
</div>

    <div class="mui-slider-item mui-fullscreen">  
        <p><img src="images/04/1.jpg" data-preview-src="" data-preview-group="1"></p>  
    </div>  
    <div class="mui-slider-item mui-fullscreen">  
        <p><img src="images/04/2.jpg" data-preview-src="" data-preview-group="1"></p>  
    </div>  

    <!--支持循环的，节点-->  
    <div class="mui-slider-item mui-fullscreen mui-slider-item-duplicate">  
        <a href="#"><img src="images/04/1.jpg"></a>  
    </div>  
</div>还是不能居中，求指点