CSS

 

#cover_div{
    position: absolute;z-index: 999999;width: 100%;height: 100%;display: none;left: 0;top: 0;min-width: 700px;min-height: 740px;      opacity: 0.01;filter: alpha(opacity = 1);background-color: #fff; display: none;}#id_messages{
    height: 70px;padding: 0px 0px 0px 25px;margin-bottom: 0px;width: 240px;border-radius: 5px;background-color: #FFF;position: absolute;z-index: 9999999;left: 50%;margin-left: -120px;top: 40%;border: 1px solid #6699CC;height /*\**/: 70px\9;display: none;}#b_txt{
    color: #fff;background-color: #6699CC;margin-top: -25px;padding-left: 25px;display: block;margin-left: -26px;width: 100%;height: 25px;border-radius: 5px;border: 1px solid grey;} #td_btn{
    width: 60px;height: 60px;}

HTML（建议放在最外层仅仅被body标签包裹）

 

 
      
 
      
    
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JQUERY

 

function  show(){  $("#cover_div").show();  $("#id_messages").show();}function  hide(){  $("#cover_div").hide();  $("#id_messages").hide();}

　

效果