쩝.....고수님들이 답글좀 다시지,,,,,바쁘신가부다..........참고만 하세요.....
초보가 공부삼아 분석좀 해봤거든요.....아래가 각각 같은겁니까????

<link rel="stylesheet" href="./style.css" type="text/css">
http://www.styleyb.net/style/css.css

또한 nav가 2군데에 있더군요.....이게 문제될거루 보입니다...

아래처럼 중복되네요....이게문제가 되는거 아닌가요???

#nav{
padding-left:20px;
}
#nav li{
float:left;
height:35px;
text-decoration:none;
}


#nav {
  float: left;
  margin: 0;
  padding: 0;
list-style: none;
font-weight: bold;
background: #fff url(img/tab_top.gif) repeat-x bottom left;
}
   
#nav li {
  float: left;
  margin: 0;
padding: 0;
color: #72611B;
  font-family: Georgia, serif;
font-size: 100%;
}

쩝..제가 소스를 열어보니....
위보듯이 2가지가 있습니다...
1가지는 화일로 있구여...
또한가지는 다른메뉴 아래에....
<ul id='nav'>  <li><a id='tab_0' href='./bbs/board.php?bo_table=01_7' onMouseOver="onTab('0');">최근뉴스</a></li>  <li><a id='tab_1' href='./bbs/board.php?bo_table=02_3' onMouseOver="onTab('1');">유행/패션</a></li>  <li><a id='tab_2' href='./bbs/board.php?bo_table=02_1' onMouseOver="onTab('2');">Star스타일</a></li>  <li><a id='tab_3' href='./bbs/board.php?bo_table=01_4' onMouseOver="onTab('3');">방문취업</a></li>  <li><a id='tab_4' href='./bbs/board.php?bo_table=01_5' onMouseOver="onTab('4');">자료공유</a></li>      <li id='tab-intro'></li>  </ul>

또한가지...
<UL id=nav>
<LI><A class=nav_on id=mynav0 onmouseover=javascript:qiehuan(0) href="http://styleyb.net"><SPAN>처음으로</SPAN></A></LI>

<LI class="menu_line"></LI><li><a href="http://styleyb.net/bbs/group.php?gr_id=01" onmouseover="javascript:qiehuan(1)" id="mynav1" class="nav_off"><span>커뮤니티</span></a></li>

<li class="menu_line"></li><li><a href="http://styleyb.net/bbs/group.php?gr_id=02" onmouseover="javascript:qiehuan(2)" id="mynav2" class="nav_off"><span>스타일</span></a></li>

쩝...이쁜그림들 많네여.........번창하세요.......그리구 새해복많이 받으세여....ㅎㅎㅎ