.demo {
    display: none;
    position: absolute;
    opacity: 0.3;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: Helvetica, "PingFang SC", "Microsoft Yahei", "微软雅黑", Arial, sans-serif;
    font-size: 14px;
}

/* 视差 */

.back-fixed {
    background-attachment: fixed;
    background-size: cover;
    background-position: center center;
}

/* 图片 */

img {
    width: 100%;
    /* fill|contain|cover */
    object-fit: cover;
    object-position: center;
}

.hidden {
    display: none !important;
}

/* 清除浮动 */

.clearfix::after {
    content: " ";
    clear: both;
    display: block;
    visibility: hidden;
    font-size: 0;
    height: 0;
}

.text-clearfix {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}

/* 清除格式 */

ul li {
    list-style: none;
}

ul li a {
    text-decoration: none;
}

/* 颜色变量 */

:root {
    --system-main: #3a5dae;
    --backdrop-color: rgba(42, 42, 42, 0.69);
    --text-darker: #2e2e2e;
    --text-menu: #6e6d7a;
    --text-lightest: #e7e9ec;
    --text-gray: #8b8b8b;
    --text-gray-dark: #727272;
    --text-dark: #494949;
    --text-blue: #0d6eb9;
    --text-blue-dark: #005197;
    --bg-gray-dark: #727272;
    --bg-blue: #0d6eb9;
    --bg-gray-light: #cccccc;
    --bg-blue-dark: #005197;
    --bg-dark: #181818;
}

/* ============= 宽度================== */

.menu-header,
.footer,
section>.content,
section>.title {
    width: 1122px;
    margin: 0 auto;
}

/* ============= 头部================== */

/* 头部 */

header {
    width: 100%;
    height: 92px;
    position: relative;
    z-index: 200;
}

header.sticky {
    position: fixed;
    top: 0;
    background: white;
    box-shadow: 0 0 7px rgba(0, 0, 0, 0.15);
}

.header-under {
    position: relative;
    top: -4px;
}

/* logo */

.menu-logo {
    float: left;
    padding: 22px 0;
}

.logo-img {
    width: 197px;
    height: 48px;
}

/* 菜单 */

.menu-header .menu-nav {
    float: right;
}

.menu-item {
    position: relative;
    display: inline-block;
    padding: 36px 20px;
}

.menu-item>a {
    color: #2e2e2e;
    font-weight: 900;
    font-size: 16px;
    margin: 0 10px;
}

.menu-item>a::after {
    content: ' ';
    width: 0;
    height: 1px;
    background: #000;
    position: absolute;
    left: 50%;
    top: 65px;
    transform: translatex(-50%);
}

.menu-item>a:hover::after,
.menu-item>a.current::after {
    content: ' ';
    transition: 0.6s ease;
    width: 60%;
}

/* 子导航 */

.menu-item ul {
    display: block;
    position: absolute;
    width: 120px;
    background: var(--system-main);
}

.menu-item ul>li:hover {
    background: var(--bg-blue-dark);
}

.menu-item ul>li>a {
    color: white;
}

.menu-sub li {
    padding: 0;
    height: 40px;
    line-height: 40px;
    text-align: center;
}

/* 子导航 */

.menu-sub {
    left: 50%;
    transform: translateX(-50%);
    transition: 0.5s;
    visibility: hidden;
    top: 120px;
    opacity: 0;
}

.menu-item:hover>.menu-sub {
    visibility: visible;
    top: 92px;
    opacity: 1;
}

.nav-sub-item {
    position: relative;
}

/* 三级导航 */

.menu-last {
    top: 0;
    left: 120px;
}

.menu-sub-item:hover>.menu-last,
.menu-last-item:hover>.menu-last {
    display: block;
}

/* 折叠按钮 */

.burger {
    display: none;
}

/* ============= 页内导航 ================== */

.menu-inners>.menu-nav {
    width: 1150px;
    margin: 0 auto;
    padding: 15px;
}

.menu-inners>.menu-nav>.nav-item {
    cursor: pointer;
    display: inline;
    margin-right: 8px;
    font-size: 12px;
    color: #cfcfcf;
}

.menu-inners>.menu-nav>.nav-item:not(:first-child)::before {
    content: '>';
    margin-right: 8px;
}

.slide-items {
    position: relative;
}

.slide-item {
    display: none;
    /* position: absolute; */
    width: 1200px;
    margin: 0 auto;
}

.slide-item.active {
    display: block;
}

.tag-nav {
    width: 1200px;
    margin: 0 auto;
    padding: 12px 40px;
    background: #fafafa;
}

.tag-nav>.nav-item {
    cursor: pointer;
    display: inline;
    margin-right: 43px;
    letter-spacing: 2px;
}

.tag-nav>.nav-item>.nav-link {
    font-size: 16px;
    color: #464646;
}

.tag-nav>.nav-item.current>.nav-link {
    color: var(--system-main);
}

/* ============= 页内 ================== */

.content-show {
    width: 100%;
    height: 205px;
    overflow: hidden;
}

.content-show>img {
    width: 100%;
    height: 205px;
}

/* ============= 内容 ================== */

.content-wrapper {
    min-height: 480px;
}

section {
    width: 100%;
    padding: 0;
}

section>h1.title {
    position: relative;
    margin: 0 auto;
    height: 30px;
}

section>h1.title>a {
    font-size: 20px;
    line-height: 20px;
    color: #2e2e2e;
    position: absolute;
    left: 30px;
}

section>h1.title::before {
    content: "";
    position: absolute;
    width: 20px;
    height: 20px;
    background-color: black;
}

section>.content {
    margin: 0 auto;
    padding: 0;
}

section>.footer {
    padding: 25px 0;
}

.btn-more {
    width: 116px;
    font-size: 16px;
    padding: 5px;
    background: white;
    border: 1px solid blue;
}

.btn-more:hover {
    color: white;
    background: blue;
}

/* ============= 页脚 ================== */

footer {
    background: #282526;
    padding-top: 48px;
    height: 280px;
}

.footer {
    margin: 0 auto;
}

.footer-content {
    float: left;
    position: relative;
    width: 630px;
    margin-left: 70px;
}

.footer-content>p {
    font-size: 14px;
    color: #e0e1e4;
    line-height: 26px;
}

.footer-menus {
    float: left;
    position: relative;
    width: 630px;
    padding-top: 50px;
}

.footer-menu {
    float: left;
    margin: 0 20px;
}

.menu-title {
    color: white;
    margin-bottom: 21px;
}

.menu-items>li {
    padding-bottom: 4px;
}

.menu-items a {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 40px;
}

.footer-code {
    float: left;
}

.footer-code>.item-code {
    float: left;
    text-align: center;
    width: 118px;
}

.footer-code>.item-code>img {
    width: 118px;
}

.footer-code>.item-code>span {
    font-size: 14px;
    color: #e0e1e4;
}

/* 返回顶部按钮 */

.scrollToTop {
    display: none;
    position: relative;
    z-index: 300;
}

.scrollToTop a {
    width: 32px;
    height: 32px;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: gray;
    color: white;
    text-decoration: none;
    position: fixed;
    bottom: 60px;
    right: 30px;
}

/* ============= 图片放大 ================== */

.img-mask {
    cursor: zoom-out;
    position: fixed;
    top: 0;
    left: 0;
    background: rgba(0, 0, 0, 0.7);
    z-index: 200;
    width: 100%;
    height: 100%;
    display: none;
}

.img-body {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

.img-body>img {
    border: 5px solid #fff;
}

.img-thumb {
    cursor: zoom-in;
}