body {
    background-color: #f5f5f5;
}

/* 内容 */
.article {
    margin: 120px auto;
    padding-bottom: 60px;
    width: 1520px;
    background-color: #fff;
}

.article .nav {
    height: 50px;
    border-bottom: 1px solid #e5e5e5;
    line-height: 50px;
}

.article .nav a:nth-child(1) {
    margin-left: 30px;
}

.article .nav a:hover {
    color: #007DFF;
}

/* 文章内容 */
.article h1 {
    margin-top: 40px;
    color: #222;
    font-size: 32px;
    font-weight: 700;
    text-align: center;
    line-height: 32px;
}

.article .tit {
    margin: 40px auto;
    font-size: 14px;
    color: #999;
    text-align: center;
}

.article .line {
    border-bottom: 1px solid #e5e5e5;
}

.article .box {
    margin: 40px auto;
    width: 1200px;
}

.article .box p {
    margin-top: 10px;
    line-height: 32px;
    text-indent: 2em;
}

.article .box h3 {
    margin-top: 25px;
    font-size: 18px;
    font-weight: 700;
}

.article .box img {
    display: block;
    margin: 25px auto;

}