@charset="UTF-8";

.navidiv{
 border-bottom: 1px solid blue;
 width: 100%;
align: left;
margin-left: 0;
padding: 0;
 line-height: 0;
 font-siza; 0.6em;
}

<link rel="stylesheet" href="../../../css/top_navi.css" type="text/css">

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１段ナビ

<div class="navidiv">
<table style="margin-left: 0; font-size: 0.8em; ">
<tbody>
<tr>
<td><a href="../../../index.html">表紙</a></td><td>＞</td>
<td><a href="../../../index.html#katudo">活動</a></td><td>＞</td>
<td><a href="../chouyou_club_mokuji.html">活動マップ</a></td><td>＞</td>
<td>朝陽合唱団</td>
</tr>
</tbody>
</table>
</div>

**************************************
２段ナビ

<div class="navidiv" style="vertical-align: middle; ">
<table style="margin-left: 0; font-size: 0.8em; height: 2.4em;">
<tbody>
<tr>
        <td rowspan="2"><a href="../../index.html">表紙</a></td>
        <td rowspan="2">＞</td>
        <td><a href="../../index.html#katudo">活動/同窓生支援</a></td>
        <td rowspan="2">＞</td>
        <td rowspan="2">水上寮</td>
      </tr>
<tr>
        <td><a href="../index.html">活動マップ</a></td>
      </tr>
</tbody>
</table>
</div>