a {
    text-decoration: none;
}

/* 主体 */
.main {
    min-height: 500px;
    text-align: center;
    display: flex;
    justify-content: center;
    align-items: center;
}
.main h3 {
    color: #333;
}
nav>main span{
    font-size: 24px;
    font-weight: bold;
    color: #795548;
    padding-left: 24px;
    padding-right: 24px;
}

nav>sub span{
    font-size: 16px;
    color: #99a;
    padding-left: 16px;
    padding-right: 16px;
}

/* 页脚 */
.footer {
    position: fixed;
    bottom: 6px;
    left: 50%;
    margin-left: -250px;
    width: 500px;
    text-align: center;
    margin-bottom: 20px;
    font-size: 16px;
    color: rgba(0, 0, 0, .54);
}

.footer a {
    color: rgba(0, 0, 0, .54);
}
.footer span {
    padding-left: 6px;
    padding-right: 6px;
}

/* 社交 */
.social {
    font-size: 20px;
}
/* 联系方式 */
.contact {
    font-size: 12px;
}

/* 分隔符 */
.separator {
    width: 500px;
    height: 1px;
    border-top: 1px solid #aaa;
    left: 50%;
    margin-left: -250px;
    margin-top: 20px;
    margin-bottom: 20px;
    position: relative
}