.nav_mid,.pro_list,.kno_list{display: none;}

.fl{float:left;}
.fr{float:right;}
.index_title{height:75px;}
.index_title img{height:100%;}
.index_title .letter_title{color:#666;font-size:16px;line-height:50px;}
.core_pro{/* height:440px; */margin-bottom:60px;margin-top:40px;}
.core_pro .core_con{margin-top:48px;}
.core_pro .core_con a{float: left;list-style: none;position: relative;margin-right: 117px;width: 280px;box-shadow: -1px 5px 16px #888888;text-decoration: none;margin-bottom:42px;}
.core_pro .core_con p{width: 100%;height: 50px;text-align: center;background: #bbb;line-height: 50px;font-size: 18px;color: #333;text-decoration: none;}
.core_pro .core_con img{width: 280px;height: 290px;}
.cert_com{background: #f3f3f3;margin-top: 400px;padding: 40px 0;}
.cert_com img.cert_img{width:100%;margin-bottom: 58px;}
.slide{background: #f3f3f3;}