.cn_tab21_1_f{ clear:both; overflow:hidden; width:1200px; height:; position:relative;  margin:0 auto; }
.cn_tab21_1_f ul{ margin:0; padding:0; padding-top:0px; padding-bottom:0px; }
.cn_tab21_1_f li{ float:left; display:block; width:; height:; border:  ; margin-left:0px; margin-bottom:0px; overflow:hidden;}
.cn_tab21_1_f li:hover{ opacity: 0.7; -ms-filter:alpha(opacity=70); filter: alpha(opacity=70); zoom:1; }