导航居中是那个 [复制链接]

版主，导航栏是向右靠齐，那个是让他居中的，我都试了，没效果麻烦给予指导：
.menu_box{clear:both;width:100%;}

                  /**********LOGO在上方样式***********/
.menu_box_style1_1{clear:both;border:0 solid #cccccc;}
.menu_box_style1_1_1{float:left;}/**********LOGO位置***********/
.menu_box_style1_1_2{float:right;padding:5px 0 0 0;}/**********标题位置***********/
.menu_box_style1_2{clear:both;text-align:left;height:27px;background:url(images/menu_bg.gif) repeat 0 0;border:0 solid #dddddd;}

.menu_style_1_first{float:left;text-align:center;padding:5px 25px 0 25px;}
.menu_style_1{float:left;text-align:center;padding:5px 25px 0 25px;background:url(images/menu_line.gif) no-repeat left top}

a.menu_1nk{colorffffff;text-decoration: none;font-weight:normal;}
a.menu_1:visited {colorffffff;text-decoration:none;font-weight:normal;}
a.menu_1:hover {colorffffff;text-decoration:underline;font-weight:normal;}

a.menu_current_1{colorffffff;text-decoration:none;font-weight:normal;}