.top{
    width: 100%;
    height: 120px;
    background-color: deepskyblue;
    margin: 0 auto;
}
.top_img{
    width: 100%;
}
.top_img img{
    width: 100%;

}

/*内容页主体部分*/
.content{
    width: 1200px;
    margin: 0 auto;
    min-height: 400px;
}

/*左边栏目导航*/
.content_l{
    float: left;
    width: 120px;
    height: 50px;
    background-color: #e6e6e6;
    text-align: center;
    align-items: center;
    line-height: 50px;
}
.content_l_top{
    color: #0079c0;
    font-size: 22px;
    font-weight: bold;
}
.content_l_content{
    background-color: #e6e6e6;
    text-align: center;
    align-items: center;
    font-size: 18px;
}
.content_l_content ul li:hover{
    background-color: whitesmoke;
    cursor: pointer;
}

/*右边主体文章*/
/* 修正右侧容器宽度 */
.content_r {
    margin-left: 30px;
    float: left;
    margin-top: 20px;
    width: calc(100% - 150px); /* 1200px - 100px - 30px */
    box-sizing: border-box;
    color: black;
    text-align: center;

}

.content_r h1{
    font-size: 22px;
    margin-top: 30px;
}

.content_r_time{
    font-size: 16px;
    display: inline-block;
    margin: 20px auto;
}

.content_r_w{
    width: 900px;
    margin: 0 auto;
    text-align: left;
    font-size: 16px;
}

.content::after {
        content: "";
        display: table;
        clear: both;
}



/*    页脚*/
.foot{
    background-image: url("../img/botton_null.jpg");
    width: 100%;
    height: 285px;
    margin-top: 60px;
}
.foot::after {
    content: "";
    display: table;
    clear: both;
}
.foot_content{
    width: 1200px;
    margin: 0 auto;
}
.foot_content_l{
    float: left;
    color: white;
    margin-top: 50px;

}
.foot_content_l div{
    margin-top: 10px;
}
.foot_content_r{
    float: right;
    color: white;
    margin-top: 60px;
    margin-right: 30px;
    font-size: 18px;
}
.foot_content_r img{
    width: 78px;
    margin-top: 5px;
    margin-right: 3px;
}