.banner{
    text-align: center;
    padding:50px 0;
    background-color: #ddd;
    color:#333;
    overflow: hidden;
}

.article{
    margin: 100px 0;
}

.article .article-title{
    text-align: center;
    margin: 50px 0;
}

.article .article-content{
    line-height: 2.0;
    margin: 50px 0;
}