关于dedecms一个问题，

如何改让背景宽度和文字一样

代码如下:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset={dede:global.cfg_soft_lang/}" />
<title>{dede:global.cfg_webname/}</title>
<meta name="keywords" content="{dede:field name='keywords'/}" />
<meta name="description" content="{dede:field name='description' function='html2text(@me)'/}" />
<link href="{dede:global.cfg_templets_skin/}/style/dedecms.css" rel="stylesheet" media="screen" type="text/css" />
<meta http-equiv="mobile-agent" content="format=xhtml;url={dede:global.cfg_mobileurl/}/list.php?tid={dede:field.id/}">
<script type="text/javascript">if(window.location.toString().indexOf('pref=padindex') != -1){}else{if(/AppleWebKit.*Mobile/i.test(navigator.userAgent) || (/MIDP|SymbianOS|NOKIA|SAMSUNG|LG|NEC|TCL|Alcatel|BIRD|DBTEL|Dopod|PHILIPS|HAIER|LENOVO|MOT-|Nokia|SonyEricsson|SIE-|Amoi|ZTE/.test(navigator.userAgent))){if(window.location.href.indexOf("?mobile")<0){try{if(/Android|Windows Phone|webOS|iPhone|iPod|BlackBerry/i.test(navigator.userAgent)){window.location.href="{dede:global.cfg_mobileurl/}/list.php?tid={dede:field.id/}";}else if(/iPad/i.test(navigator.userAgent)){}else{}}catch(e){}}}}</script>
</head>
<body class="articlelist">
{dede:include filename="head.htm"/}
<!-- /header -->
<div class="w960 center clear mt1">
<div class="pleft">
<div class="place"> <strong>当前位置:</strong> {dede:field name='position'/} </div>
<!-- /place -->
<div class="listbox">
<ul class="e2">
{dede:list pagesize='10'}
<li> [field:array runphp='yes']@me = (empty(@me['litpic']) ? "" : "<a href='{@me['arcurl']}' class='preview'><img src='{@me['litpic']}'/></a>"); [/field:array]
[<b>[field:typelink/]</b>] <a href="[field:arcurl/]" class="title">[field:title/]</a> <span class="info"> <small>日期：</small>[field:pubdate function="GetDateTimeMK(@me)"/] <small>点击：</small>[field:click/] <small>好评：</small>[field:scores/] </span>
<p class="intro"> [field:description/]... </p>
</li>
{/dede:list}
</ul>
</div>
<!-- /listbox -->
<div class="dede_pages">
<ul class="pagelist">
{dede:pagelist listitem="info,index,end,pre,next,pageno,option" listsize="5"/}
</ul>
</div>
<!-- /pages -->
</div>
<!-- /pleft -->
<div class="pright">
<div>
<dl class="tbox">
<dt><strong>栏目列表</strong></dt>
<dd >
<ul class="d6">
{dede:channel type='son' currentstyle="
<a href='typelink' class='thisclass'>typename</a>
"}
<li ><a href='[field:typeurl/]'style="float:none;clear:both;">[field:typename/]</a></li>
{/dede:channel}
</ul>
</dd>
</dl>
</div>
<div class="commend">
<dl class="tbox light">
<dt class='light'><strong>推荐内容</strong></dt>
<dd class='light'>
<ul class="d4">
{dede:arclist flag='c' titlelen=42 row=6}
<li><a href="[field:arcurl/]">[field:title/]</a>
<p>[field:description function='cn_substr(@me,80)'/]...</p>
</li>
{/dede:arclist}
</ul>
</dd>
</dl>
</div>
<!-- /commend -->
<div class="hot mt1 light">
<dl class="tbox">
<dt class='light'><strong>热点内容</strong></dt>
<dd class='light'>
<ul class="c1 ico2">
{dede:arclist row=10 orderby=click}
<li><a href="[field:arcurl/]">[field:title/]</a></li>
{/dede:arclist}
</ul>
</dd>
</dl>
</div>

</div>
<!-- /pright -->
</div>
{dede:include filename="footer.htm"/}
<!-- /footer -->
</body>
</html>

css :

/list_nav
------------------/
.d6{
width:100%;
overflow:hidden;
padding-bottom:6px;
clear:both;
display:inherit;
}
.d6 li{

margin:6px 0 1px 8px;
display:block;
}
.d6 li a{
width:200px;
padding-left:20px;
height:26px;
line-height:26px;
display:block;
background:url(../images/green_skin.png) -42px -222px no-repeat;
color:#316301;
}
.d6 li a:hover{
text-decoration:none;
}
.d6 li a.thisclass{
background:url(../images/green_skin.png) -42px -249px no-repeat;