* {
    margin: 0;
    padding: 0;

}

ul {
    list-style: noe;
}

a {
    text-decoration: none;
}

#headerLayout {
    width: 100%;
    height: 83px;
    box-shadow: 1px 1px 10px rgba(0, 0, 0, 0.3);
}

.header {
    height: 83px;
    line-height: 83px;
    background: white;
    position: fixed; /*固定*/

}

.header a {
    float: left;
    margin-top: 10px;

}

.header ul {
    float: right;
}

.header ul li {
    float: left;
    margin: 0 20px;
    color: #000;
}
.channel ul {
text-align: center;
    padding-top: 100px;
}
.channel ul li{
    display: block;
    margin: 0 10px;
    max-width: 24%;/*如果宽度大于24%，以24%的宽度进行显示，如果《24%，以本身的宽度显示*/
}

.channel ul li img {
    width: 100%;  /*和li的宽度达成一致*/
}












@media scren and (min-width: 1000px) {
    .header {
        width: 1000px;
        margin: 0 auto;
    }
}