* {
    margin: 0px;
    padding: 0px;
}

#nav_box {
    /* width: 75%; */
    height: 36px;
    padding-left:3%;
    padding-right:3%;
    background-color: rgb(180, 31, 35);
}

li {
    list-style: none;
}

a {
    text-decoration: none;
}

#nav {
    /* 设置导航栏宽高，水平居中 */
    width: auto;
    height: 36px;
    line-height: 36px;
    text-align: center;
    margin: 0px;
    padding: 0px;
    display: flex;
    margin: 0 auto;
    justify-content: space-around;
}

#nav>li {
    /* 左浮动，将li标签水平排列 */
    height: 60px;
    line-height: 60px;
    text-align: center;
    float: left;
    z-index: 99;
}

#nav li {
    /* margin: 0px 10px; */
    z-index: 999;
    min-width: 100px;
    height: 50px;
    line-height:50px;
    text-align: center;
    background: rgb(180,32,35);
}

#nav li a:hover {
    text-decoration: none;
}

#nav>li a {
    color: white;
}

#nav>li {
    min-width: 100px;
    text-overflow: ellipsis;
    white-space: nowrap;
    position: relative;
    /* 这个可能后面需要改一下规则 */
}

#nav>li a {
    overflow: hidden;
    text-overflow: ellipsis;
    text-wrap: nowrap;
    width: 8em;
    display: inline-block;
}

#thinav>li {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}

#nav li:hover {
    /* 鼠标指向该位置时的背景颜色 */
    background-color: crimson;
}

#subnav {
    /* 隐藏二级列表 */
    display: none;
    position: absolute;
    top: 36px;
}

#nav li:hover>#subnav {
    /* 鼠标指向该位置时二级列表出现 */
    display: block;
}


#subnav>li {
    /* 先对二级列表的<li>标签定位 */
    position: relative;
}

#subnav>li:hover>#thinav {
    /* 鼠标在指定位置时三级列表出现 */
    display: block;
}

#thinav {
    /* 对三级列表定位并隐藏 */
    position: absolute;
    top: 0px;
    left: 8em;
    display: none;
}

#input_box {
    margin-top: 17px;
    height: 24px;
    background-color: rgba(255, 255, 255, 0.5);
    border-radius: 30px;
    text-align: center;
    line-height: 24px;
    color: white;
    padding-right: 10px;
    padding-left: 10px;


}

#input::placeholder {
    color: #ffffff;
    text-align: start;
}

#input {
    width:8em;
    background-color: transparent;
    color: white;
    border: 0;
    /*border-top-left-radius: 30px;*/
    /*border-bottom-left-radius: 30px;*/
    font-size: 14px;
    text-align: left;
}

.enabled {
    border: none;
    height: 70%;
    text-align: center;
    font-size: 14px;
    background-color: #fff;
    border-bottom: 1px solid #ccc;
    outline: none;
}

div.first_img img:first-child {
    width: 100%;
    height:100%;
    display: block;
    margin-left: auto;
    margin-right: auto;
}

div.first_img img:nth-child(2) {
    z-index: 99;
    width: 30%;
    position: absolute;
    left: 10%;
    top: 20px;
}
div.first_img img:nth-child(3) {
    z-index: 99;
    width: 30%;
    position: absolute;
    left: 40%;
    top: 20px;
}