html,
body {
    margin: 0;
    padding: 0;
    overflow: visible !important;
    min-height: 100vh;
}


header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: #111;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    z-index: 999;
}

.nav_container {
    width: 100%;
    max-width: 2560px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
    padding: 0 100px;
}

/* 在 header.html 的 CSS 中 */
nav,
.navbar,
.dropdown-menu {
    pointer-events: auto;
    /* 核心：恢复导航和二级菜单的鼠标交互 */
}

/* LOGO */
.logo {
    display: flex;
    align-items: center;
    margin-right: 7%;
}

.logo img {
    height: 60px;
}

/* 导航菜单 - 核心修复 */
.nav_menu {
    /* flex: 1;
    display: flex;
    list-style: none;
    align-items: center;
    gap: 13px;
    height: 80px; */

    display: flex;
    list-style: none;
    align-items: center;
    gap: 17px;
    height: 80px;
    margin: 0 auto;
    width: 819px;

}

.nav_item {
    min-width: 114px;
    position: relative;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #9e9ea0;
    text-decoration: none;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.1em;
    transition: color 0.3s ease;
    font-family: 思源宋体;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
}

.nav_itemlong1 {
    margin-right: 30px;
}

.nav_itemlong2 {
    margin-right: 20px;
}

.nav_item a {
    color: #9e9ea0;
    text-decoration: none;
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.1em;
    transition: color 0.3s ease;
    font-family: 思源宋体;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.nav_item a:hover {
    color: #e61314;
}

.nav_item.active a {
    color: #fff;
}

.nav_item.active {
    color: #fff;
    background: url(../imgs/tzh2605sy_headnavyes.png) center center no-repeat;
}


.nav_item:hover .dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown li a {
    display: block;
    padding: 10px 20px;
    color: #ccc;
    font-size: 14px;
    transition: all 0.2s ease;
}

.dropdown li a:hover {
    background-color: rgba(255, 68, 68, 0.1);
    color: #ff4444;
}

/* 右侧操作区 */
.nav_right {
    display: flex;
    align-items: center;
    gap: 20px;
}

.header_btn {
    width: 148px;
    height: 45px;
    padding-left: 55px;
    display: flex;
    align-items: center;
    gap: 8px;
    color: #fff;
    text-decoration: none;
    font-size: 18px;
    font-weight: 600;
    background: url(../imgs/tzh2605sy_headhybg.png) center center no-repeat;
    font-family: 思源宋体;
    letter-spacing: 1px;
    cursor: pointer;
}

.header_btn:hover {
    border-color: #ff4444;
    color: #ff4444;
}

.header_zhuxiao {
    display: none;
}

.member_down {
    float: right;
    cursor: pointer;
}

/* 移动端汉堡菜单 */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background-color: #fff;
    border-radius: 2px;
    transition: all 0.3s ease;
}


.nav_mask {
    width: 100%;
    left: 0;
    position: fixed;
    background: rgba(0, 0, 0, 0.6);
    top: 80px;
    display: none;
    z-index: 999;
    box-sizing: border-box;
    display: none;
}

.nav_mask a {
    width: 100%;
    display: block;
    text-align: center;
    color: #fff;
    line-height: 40px;
    font-size: 20px;
    font-family: 思源宋体;
    font-weight: 550;
}

@media (max-width: 1024px) {
    .nav_menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        height: 100vh;
        background: #000;
        flex-direction: column;
        padding-top: 80px;
        transition: right 0.3s ease;
        z-index: 999;
    }

    /* 打开状态，滑入屏幕 */
    .nav_menu.show-mobile {
        right: 0;
    }

    .nav-mask.show-mask {
        display: block;
    }
}

/* 响应式适配 */
@media (max-width: 1200px) {
    .nav_menu {
        display: none;
    }

    .hamburger {
        display: flex;
    }



    .nav_container {
        padding: 0 20px;
    }
}

@media (max-width: 768px) {
    .logo img {
        height: 50px;
    }

    .header_btn {
        width: 152px;
        font-size: 16px;
    }

    .member_down {
        /* display: none; */
    }
}

/* 导航栏容器 */
nav,
.navbar {
    height: 80px;
    overflow: visible !important;
    /* 核心：允许二级菜单溢出 iframe 边界 */
}

/* 二级菜单 */
.submenu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    z-index: 1001;
    /* 确保在最上层 */
}

/* 悬停显示 */
.nav-item:hover>.submenu {
    display: block;
}


/* 导航栏容器 - 核心修复 */
.nav_container {
    width: 100%;
    max-width: 2560px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 80px;
    padding: 0 100px;
    overflow: visible !important;
    /* ⚠️ 必须加上这个，否则二级菜单会被 iframe 边界切掉 */
}

/* 下拉菜单 */
.dropdown {
    position: absolute;
    top: 100%;
    left: -20px;
    background-color: #1a1a1a;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-top: 2px solid #ff4444;
    padding: 10px 0;
    list-style: none;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.3s ease;
    min-width: 160px;
    z-index: 1001;
    /* 确保在最上层 */
    pointer-events: auto;
    /* 确保二级菜单可交互 */
}

.nav_item:hover .dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}