导航栏内设置字体与图标居中

<nav class="navbar navbar-inverse  blue"  role="navigation">

     <div class="container-fluid">

      <div class="navbar-header">

       <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1">

       </button>

       <span><a class="navbar-brand" href="#">

        <img alt="Brand" height="30px" src="images/bootstrap-logo.png">

       </a>

       Angulr</span>

    </div>

  </div>

</nav>