*{margin:0;padding:0;border:0;}
#div_center { width:730px; height:29px; margin-left: auto;margin-right:auto;} /*?????????;background:003399; ??????,????*/ 
#nav { line-height: 23px; list-style-type: none; margin-top:7px;  }         /*????????;???5px;*/   
#nav a { display: block; width: 85px; text-align:center; font-size:12px;} /*??????????:??????,????,????*/ 
#nav a:link { color:#000; text-decoration:none;margin:0;}     /* ?????? */   
#nav a:visited {color:#000;text-decoration:none;margin:0;}    /* ?????? */ 
#nav a:hover {color:#fff;text-decoration:none;}                /* ?????? */

#nav li {float: left; }                   /* ?????? */ 
#nav li a:hover{font-weight:bold;background:#636363;}     /* ?????????????? */ 
#nav li ul {line-height: 24px; background-color:#fff; filter: Alpha(Opacity=60);;position:absolute; list-style-type: none;text-align:left;left: -999em; width:110px; position: absolute;;}             /*????????:??24px;????;????;????;??????,?????,??????,????#003399;???1???*/

#nav li ul a{display:block; width: 110px;text-align:left;padding-left:2px;}                 /* ????????;????????,???2 */
#nav li ul a:link {color:#000000; text-decoration:none;}                                   /* ?????? */ 
#nav li ul a:visited {color:#000000;text-decoration:none;}                                 /* ?????? */
#nav li ul a:hover {color:#FFF;text-decoration:none;font-weight:normal;background:#555555;}/* ?????? */

#nav li:hover ul {left: auto;}
#nav li.sfhover ul {left: auto;}
#content {clear: left;}

.alpha1{
width:300px;
height:200px;
background-color:#FF0000;
filter: Alpha(Opacity=30);
}
.ap2{
position:relative;
}