导航栏带子导航菜单并且高亮

<div class="nav">
        <ul>
            <li>
                <a href="{siteurl($siteid)}" {if !$catid} class="hover"{/if}>首页</a></li>
            {pc:content action="category" catid="0" num="20" siteid="$siteid" order="listorder ASC"}
                {loop $data $k $r}
                <li>
                    <a href="{$r['url']}" {if $catid==$r[catid] || $top_parentid==$r[catid]} class="hover"{/if} >{$r[catname]}</a> 
                {pc:content action="category" catid="$k" num="20" siteid="$siteid" order="listorder ASC"}
                <ul>
                    {loop $data $r}
                    <li><a href="{$r['url']}">{$r[catname]}</a></li>
                    {/loop}
                </ul>
                {/pc}</li>
                {/loop}
            {/pc}
        </ul>
    </div>