鼠标提上去弹出提示层（定位）

希望的效果如图：

网上找了各纯css的做了下修改：

代码如下：

 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
 <style> 
.logo1{
     width:150px; 
     height:60px; 
     float:left 
}
a.alt{
position:relative;
background-color:#fff;
float:left;
width:158px;
height:60px;
border:1px solid #ccc;
text-align:center;
text-decoration:none;
color:#333333;
}
a.alt:hover{background:#fff; text-decoration:none;z-index:2;}
a.alt div{display:none;}
a.alt:hover div{
     display:block; 
     position:absolute; 
     top:-1px; 
     left:-300px; 
     width:300px; 
     height:300px; 
     border:2px solid #000; 
     z-index:1; 
     background-color:#fff; 
}
.brandAlertCen{
     border:1px solid #000; 
     width:300px; 
     height:300px; 
}
 </style> 
 <div style="margin-left:500px;width:300px;height:auto"> 
     <div class="logo1"><a class='alt' href="#"><div class="brandAlertCen">专注于网页特效及广告代码。<br /><img src="http://p0.jmstatic.com/pop_feature/12812/new_pre_pic.png" width="280" /></div><img src="http://images.253.com/upload/brandImages/139865426888345.jpg" /></a></div> 
     <div class="logo1"><a class='alt' href="#"><div class="brandAlertCen">专注于网页特效及广告代码。<br /><img src="http://p0.jmstatic.com/pop_feature/12812/new_pre_pic.png" width="280" /></div><img src="http://images.253.com/upload/brandImages/139865426888345.jpg" /></a></div> 
     <div class="logo1"><a class='alt' href="#"><div class="brandAlertCen">专注于网页特效及广告代码。<br /><img src="http://p0.jmstatic.com/pop_feature/12812/new_pre_pic.png" width="280" /></div><img src="http://images.253.com/upload/brandImages/139865426888345.jpg" /></a></div> 
     <div class="logo1"><a class='alt' href="#"><div class="brandAlertCen">专注于网页特效及广告代码。</div><img src="http://images.253.com/upload/brandImages/139865426888345.jpg" /></a></div> 
     <div class="logo1"><a class='alt' href="#"><div class="brandAlertCen">专注于网页特效及广告代码。</div><img src="http://images.253.com/upload/brandImages/139865426888345.jpg" /></a></div> 
 </div> 