经典 IE6 float bug 解决办法

 .section1
        {
            
            background-color:White;
        }
        .section1 h4
        {
            padding:0 10px;
            
            line-
            color:#be4022;
            border-bottom:1px solid #CE626E
        }
        .left
        {
            width: 220px;
            float: left;
            margin-right: 10px;
            border:1px solid #dbdada;
            display:inline;
        }
        .right-extra
        {
            float: right;
            width: 720px;
        }
        .middle
        {
            float: left;
            width: 410px;
        }
        .right
        {
            float: right;
            width: 288px;
            border:1px solid #dbdada;
        }
        .right li
        {
            
            line-
        }
        .clr {
    clear: both;
    display: block;
    font-size: 0;
    
    line-
    overflow: hidden;
}

<div>
<div class="right-extra">
                <div class="middle" style="">
                    22</div>
                <div class="right" style="">
                    <h4>
                        商家促销</h4>
                    <ul>
<li>xxxxxxx</li>        
<li>xxxxxxx</li> 
<li>xxxxxxx</li> 
                  </ul>
                    <ul>
                        <li></li>
                    </ul>
                </div>
                <span class="clr"></span>
            </div>
            <div class="left" style="">
                <h4>
                    全部分类</h4>
            </div>
            <span class="clr"></span>
</div>