* {
    margin: 0;
    padding: 0;
    font-family: "微软雅黑";
    -moz-box-sizing: border-box;
    -webkit-box-sizing: border-box;
    -o-box-sizing: border-box;
    -ms-box-sizing: border-box;
    box-sizing: border-box;
}

img {
    display: inline-block;
    border: 0;
}

li {
    list-style: none;
}

a {
    text-decoration: none;
    color: black;
}

.w {
    width: 1200px;
    margin: 0 auto;
}

.clearfix:after {
    /*伪元素是行内元素 正常浏览器清除浮动方法*/
    content: "";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}

.clearfix {
    *zoom: 1;
    /*ie6清除浮动的方式 *号只有IE6-IE7执行，其他浏览器不执行*/
}