html body {
    background-image: url("../images/bg_img_download.png");
    background-size: 100%;
    background-repeat: no-repeat;
}

.main {
    /*background-color: #fff;*/
}

.xiazai {
    /*height: 20px;*/
    line-height: 20px;
    padding: 10px 20px;
}

.xiazai .home1 {
    color: #4e9be9;
}

.xiazai span {
    color: #ccc;
    font-size: 12px;
}

.left h1 {
    font-size: 16px;
}

.zhinan {
    display: flex;
    position: relative;
}

.left {
    position: absolute;
    margin-left: -20px;
    width: 220px;
    height: 400px;
    background-color: #4e9be9;
    color: #fff;
    background: linear-gradient(#4e9be9, #5667cf);

}

.left h1 {
    padding: 30px;
    padding-left: 30px;
}

.left .left-icon {
    font-size: 22px;
    padding-right: 10px;
}

.left li {
    height: 50px;
    line-height: 50px;
    padding-left: 30px;
    font-size: 16px;
}

.left ul li a {
    display: inline-block;
    height: 50px;
    line-height: 50px;
    color: #fff;
}

.left ul li:hover {
    background: linear-gradient(to left, rgba(0, 0, 0, 0), rgba(255, 255, 255, .2), rgba(0, 0, 0, 0));
}

.left-img {
    position: absolute;
    left: 0;
    top: 393px;
    right: 0;
    bottom: 0;
    width: 20px;
}

.left-img img {
    width: 100%;
}

.right {
    /*flex: 1;*/
    background-color: #fff;
    /*height: 2000px;*/
    margin-left: 216px;
}

.active {
    background: linear-gradient(to left, rgba(0, 0, 0, 0), rgba(255, 255, 255, .2), rgba(0, 0, 0, 0));
}

.left a {
    text-decoration: none;
}