main {}

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

nav {
    background: rgb(248, 249, 252);
    font-size: 16px;
    font-weight: 500;
    color: rgba(51, 51, 51, 1);
    height: 62px;
    line-height: 62px;
}

nav a {
    color: rgba(153, 153, 153, 1);
}

nav .box {
    margin: 0 auto;
    width: 1200px;
}

.rich {
    padding-top: 36px;
    padding-bottom: 60px;
}