fix nav

resources/views/admin/index.blade.php

@@ -62,11 +62,7 @@
                     <a href="#">
                         <i class="fa fa-cogs"></i>
                         <span>系统设置</span>
-                        <i class="fa fa-angle-left pull-right"></i>
                     </a>
-                    <ul class="treeview-menu">
-                        <li><a href="#"><i class="fa fa-circle-o"></i>计算公式</a></li>
-                    </ul>
                 </li>
                 <li class="treeview">
                     <a href="{{ url('/user_list') }}">