*{margin:0px;padding:0px; }
body{font-family: Arial;}
#main{ position:absolute;left:0px;right:0px;margin:0 auto;width:900px;height:600px;font-size:16px;border:1px solid #ccc;background:url(../images/bg.png);border-radius:10px;overflow:hidden;color: #fff;}
#subHead{position: absolute;top: 40px;left:0px;font-size: 35px;width: 900px;text-align: center;font-weight: bold;}
#fileList{position: absolute;top: 85px;left: 0px;background: url(../images/1.png);width:873px;height: 450px;right: 0;margin: auto;background-size: 100% 100%;}
.listItems{position: absolute;font-size: 30px;text-align: center;width: 420px;border: 0px solid;font-weight: bold;}
#list_1{top: 80px;left: 10px;width: 200px;}
#list_2{top: 80px;left: 220px;width: 200px;}
#list_3{top: 80px;right: 10px;}
.listItems li{cursor:pointer;list-style-type: none;margin: 24px 0px 24px 0px;}
.listItems li:hover{color: #000099;}
.pagenav{position: absolute;right: 10px;font-weight: bold;font-size: 25px;cursor: pointer;color: #000;}
#mainGrade{top: 560px;display: none;}

#iframe{position: absolute;top:0px;left:0px;border:none;width:900px;height:600px;display: none;}