setting页面导航栏Title不居中

setting页面中，导航栏如果在右侧放置“保存”按钮，如下。会出现Title不能居中的问题。看看啥情况？

<div class="mui-navbar-inner mui-bar mui-bar-nav">
<button type="button" class="mui-left mui-action-back mui-btn mui-btn-link mui-btn-nav mui-pull-left">
<span class="mui-icon mui-icon-left-nav"></span>返回
</button>
<h1 class="mui-center mui-title">Title</h1>
<button type="button" class="mui-right mui-btn-link mui-btn-nav mui-pull-right">保存</button>
</div>