背景透明而字不透明

<div class="footer">
    <div class="main100 ft"></div>
    <div class="main100 foot">
        <div class="main bff p_bo_10 c_fff">
            <ul class="te_ce m_to_10">
                <a href="#" class="m_lere_10 c_fff" rel="nofollow">关于我们</a><span>|</span>
            </ul>
        </div>
    </div>
</div>

.footer{ position:relative; overflow:hidden;}
.ft{ height:75px; background:#fff; opacity:0.3; filter:alpha(opacity=30);}
.foot{ height:75px; position:absolute; left:0; top:0; overflow:hidden;}