* {
    margin: 0;
    padding: 0;
}
a {
    text-decoration: none;
    color: #fff;
}
li {
    list-style: none;
}
.w {
    width: 1920px;
    margin: 0 auto;
}
.ww {
    width: 776px;
    margin: 0 auto;
}
.clearfix::after {
    content: '';
    height: 0;
    line-height: 0;
    visibility: hidden;
}