div设置margin:0 auto;后弹出框错位，求解！该如何处理

<div id="sub-header">
    <div class="layout">
        <a id="sub-logo" href="{$_G[siteurl]}"><img src="/style/images/small_logo.jpg" title="$_G['setting']['bbname']" alt="$_G['setting']['bbname']" /></a>
        <div id="sub-menu">
            <dl class="menu-nav">
                <dt><a href="{$_G[siteurl]}" onMouseOver="showMenu({'ctrlid':'twt','duration':'2'});">123</a></dt>
                <dd id="twt_menu" class="nav-floor" style="display:none;">
                    <ol>
                    <!--{eval $i = 1;}-->
                    <!--{loop $catlist $cat}-->
                        <!--{eval $forumurl = !empty($forum['domain']) && !empty($_G['setting']['domain']['root']['forum']) ? 'http://'.$forum

['domain'].'.'.$_G['setting']['domain']['root']['forum'] : 'forum.php?mod=forumdisplay&fid='.$cat[fid];}-->
                    <li><a href="$forumurl" title="$cat[name]"><!--{if $i <= '9'}-->$number{$i}<!--{else}-->{$i}<!--{/if}-->#$cat[name]</a></li>
                    <!--{eval $i ++;}-->
                    <!--{/loop}-->
                    </ol>
                </dd>
            </dl>
        </div>
<!--{if $_G['setting']['search']}-->
    <!--{eval $slist = array();}-->
    <!--{if $_G['fid'] && $_G['forum']['status'] != 3 && $mod != 'group'}--><!--{block slist[forumfid]}--><li><a href="javascript:;" rel="curforum" class="curtype">{lang 

search_this_forum}</a></li><!--{/block}--><!--{/if}-->
    <!--{if $_G['setting']['portalstatus'] && $_G['setting']['search']['portal']['status'] && ($_G['group']['allowsearch'] & 1 || $_G['adminid'] == 1)}--><!--{block slist

[portal]}--><li><a href="javascript:;" rel="article"{if CURSCRIPT == 'portal'} class="curtype"{/if}>{lang article}</a></li><!--{/block}--><!--{/if}-->
    <!--{if $_G['setting']['search']['forum']['status'] && ($_G['group']['allowsearch'] & 2 || $_G['adminid'] == 1)}--><!--{block slist[forum]}--><li><a href="javascript:;" 

rel="forum"{if (CURSCRIPT == 'forum' && !$_G['fid']) || (CURSCRIPT == 'home' && in_array($do, array('thread', 'activity', 'poll', 'reward', 'debate', 'trade')))} 

class="curtype"{/if}>{lang thread}</a></li><!--{/block}--><!--{/if}-->
    <!--{if $_G['setting']['homestatus'] && $_G['setting']['search']['blog']['status'] && ($_G['group']['allowsearch'] & 4 || $_G['adminid'] == 1)}--><!--{block slist

[blog]}--><li><a href="javascript:;" rel="blog"{if CURSCRIPT == 'home' && $do == 'blog'} class="curtype"{/if}>{lang blog}</a></li><!--{/block}--><!--{/if}-->
    <!--{if $_G['setting']['homestatus'] && $_G['setting']['search']['album']['status'] && ($_G['group']['allowsearch'] & 8 || $_G['adminid'] == 1)}--><!--{block slist

[album]}--><li><a href="javascript:;" rel="album"{if CURSCRIPT == 'home' && $do == 'album'} class="curtype"{/if}>{lang album}</a></li><!--{/block}--><!--{/if}-->
    <!--{if $_G['setting']['groupstatus'] && $_G['setting']['search']['group']['status'] && ($_G['group']['allowsearch'] & 16 || $_G['adminid'] == 1)}--><!--{block slist

[group]}--><li><a href="javascript:;" rel="group"{if CURSCRIPT == 'group' || $_G['basescript']=='group'} class="curtype"{/if}>$_G['setting']['navs'][3]['navname']</a></li><!--

{/block}--><!--{/if}-->
    <!--{block slist[user]}--><li><a href="javascript:;" rel="user"{if (CURSCRIPT == 'home' && !in_array($do, array('blog', 'album', 'thread', 'activity', 'poll', 'reward', 

'debate', 'trade'))) || $mod == 'ranklist'} class="curtype"{/if}>{lang users}</a></li><!--{/block}-->
<!--{/if}-->
            <!--{if $_G['setting']['search'] && $slist}-->
            <div id="sub-search">
                <form id="scbar_form" method="{if $_G[fid] && !empty($searchparams[0])}get{else}post{/if}" autocomplete="off" onsubmit="searchFocus($('scbar_txt'))" action="{if 

$_G[fid] && !empty($searchparams[0])}$searchparams[0]{else}search.php?searchsubmit=yes{/if}" target="_blank">
                    <input type="hidden" name="mod" id="scbar_mod" value="search" />
                    <input type="hidden" name="formhash" value="{FORMHASH}" />
                    <input type="hidden" name="srchtype" value="title" />
                    <input type="hidden" name="srhfid" value="$_G[fid]" id="dzsearchforumid" />
                    <input type="hidden" name="srhlocality" value="$_G['basescript']::{CURMODULE}" />
                    <!--{if !empty($searchparams[1])}-->
                        <!--{loop $searchparams[1] $key $value}-->
                        <!--{eval $srchotquery .= '&' . $key . '=' . $value;}-->
                        <input type="hidden" name="$key" value="$value" />
                        <!--{/loop}-->
                        <input type="hidden" name="source" value="discuz" />
                        <input type="hidden" name="fId" value=""  id="cloudsearchforumId" />
                        <input type="hidden" name="q" id="cloudsearchquery" value="" />
                    <!--{/if}-->
                    <input type="text" name="srchtxt" id="scbar_txt" autocomplete="off" class="sub-search-key" placeholder="搜你想要的...">
                        <dl class="sub-serach-switch">
                            <dt id="scbar_type" onclick="showMenu(this.id)" hidefocus="true">{lang search}</dt>
                        </dl>
                    <input type="submit" name="searchsubmit" id="scbar_btn" class="sub-search-btn" value="true">
                </form>
            </div>
            <!--{/if}-->
            <ul id="scbar_type_menu" class="p_pop" style="display: none; margin-top:0;"><!--{echo implode('', $slist);}--></ul>
            <script type="text/javascript">
                initSearchmenu('scbar', '$searchparams[0]');
            </script>
    </div>
</div>