<div class="tabpane">
<ul class="tabnav">
<li>公告</li>
<li>規則</li>
<li>論壇</li>
<li>安全</li>
<li>公益</li>
</ul>
</div>
.tabnav{
display:flex;
flex-flow:row nowarp;
justify-content:space-around;
}
