关于两个div并排，已经有设float:left，宽度也没有超过限制，为什么会出现如图的结果？
<style type="text/css">
div{text-align:center;
}
.fundMsg{ float:left;
width:80px;
height:20px;
background-color: #FFFF66;
border:1px solid #333333;
border-bottom:none;
margin:10px;
margin-bottom:0px;
position:relative;
z-index:2;
}
.score{ float:left;
width:50px;
height:20px;
background-color:#EEEEEE;
border:1px solid #333333;
border-bottom:none;
margin:10px;
margin-bottom:0px;
position:relative;
z-index:-1;
}
.content{ width:340px;
height:400px;
background-color:#FFFF66;
border:1px solid #333333;
position:relative;
top:25px;
z-index:0;
}
* {margin:0px;padding:0px;font:12px "宋体","Arial",sans-serif;list-style:none;float:none;}ul{height:auto;width:auto; background-color: #FFFF66;margin:20px;padding:0px;}
li{height:30px;width:auto;border:1px solid #858585;vertical-align:middle;border-top:none;padding:0px;margin:0px;}
li span{float:left;width:50px;background:#efefef;height:30px; text-align:center;border-right:1px solid #000;margin-right:5px;padding:0px;margin:0px; overflow:hidden;}
.bordertop{border-top:1px solid #000;}
.all .content ul li{width:102px;
}
.all .content .ulc ul li{width:255px;
}
.bordertop span{background-color:#666666;
}
.img{width:100px;
height:100px;
padding:0;
margin:0;
}
</style><title>无标题文档</title>
</head>
<body><div class="all">
<div class="title">
<div class="fundMsg">基本信息</div>
<div class="score">成绩</div>
</div>
<div class="content" id="fundmsg">
<div style="float:left">
<ul>
<li class="bordertop"><span>姓名</span><span>学号</span></li>
<li><span>张小山</span><span>001</span></li>
<li><span>李小石</span><span>002</span></li>
<li><span>黄小明</span><span>003</span></li>
<li><span>林小强</span><span>004</span></li>
<li><span>郭宁</span><span>005</span></li>
<li><span>林杰</span><span>006</span></li>
<li><span>敏敏</span><span>007</span></li>
<li><span>白素</span><span>008</span></li>
<li><span>青云山</span><span>009</span></li>
<li><span>水灵</span><span>010</span></li>
</ul>
</div>
<div class="img" style="float:left">
<img src="images/1 (1).jpg" border="0" width="100px" height="100px" />
</div>
</div>
</div>
width:340px;
height:400px;
background-color:#FFFF66;
border:1px solid #333333;
position:absolute;
top:25px;
left:0px;
z-index:0;
}
