/*吸顶*/
.top {width: 100%; height: 100px; line-height: 100px; position: fixed; z-index: 99999; left: 0; top: 0}
.top {background: #fff; box-shadow: 0px 2px 4px rgba(50,50,50,0.2); -webkit-box-shadow: 0px 2px 4px rgba(50,50,50,0.2); -moz-box-shadow:0px 2px 4px rgba(50,50,50,0.2);}
.top{padding: 0 20px; font-size: 24px;}
.bg_top{background: url(../images/bg_top1.jpg) #9999FF top center no-repeat ; /* opacity: 0.5; filter: alpha(opacity=50); IE8 及更早的版本 */}