body {
    margin: 0;
}

 
.topMain_mnav {
    font: 13px/23px Arial,sans-serif;
    margin-top: 8px;
    display: inline-block;
    position: relative;
    color: #222;
    margin-left: 15px;
}

.maindir {
    margin: 0 auto;
    border: 0px solid #000;
    width: 95%;
     
}

        a {
            text-decoration: none;
             
        }
   
        a:hover {color: blue; }    /* 鼠标悬浮在上的链接 蓝色 */