背景半透明，图片不透明样式设置

<style type="text/css">
   .dmenu{
     text-align:center;
      width:100%;
      margin-bottom: 13px;
      margin-top: 8px;
      cursor: hand;
   }
   .dmenu img{
      filter:alpha(opacity=100);
      opacity:1;
      width:78px;
      height: 78px;
   }
   .dmenu span{
       font-size:15px;
       font-weight:bold;
       display: block;
       font-style:'黑体';
       margin: 0;
       padding:0;
   }
  
</style>

 

<div style="width:150px;position: absolute;right: 0;border:1px solid black;height:99.3%;">
          <div style="width:100%;height: 100%;background-color:#7c7c7c;filter:alpha(opacity=80); opacity:0.8;position: absolute;z-index: -1;"></div>
          <div class="dmenu"  onclick="mnlist1()" >
               <img src="images/clock1.png"/><br>
               <span>实时数据</span>
          </div>
          <div class="dmenu" onclick="mnlist2()">
              <img src="images/alarm.png" /><br>
              <span>报警处置</span>
          </div>
          <div class="dmenu" onclick="mnlist3()">
              <img src="images/e_mail.png" /><br>
              <span>处置日志</span>
          </div>
          <div class="dmenu" onclick="mnlist4()">
              <img src="images/statistics1.png"/><br>
              <span>数据统计</span>
          </div>
      </div>