/* ========== 全站共用变量（必须最先引入，所有页面共用配色 ========== */
:root {
    --primary-blue: #0b2545;
    --accent-blue: #134074;
    --light-blue: #8da9c4;
    --dark-charcoal: #1d2d44;
    --pure-white: #ffffff;
    --border-color: #e2e8f0;
    --text-main: #334155;
    --alert-red: #d9383a;
}

/* ========== 全局基础重置（所有页面通用） ========== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
body {
    font-family: "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
    color: var(--text-main);
    background-color: var(--pure-white);
    line-height: 1.6;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
}
img {
    max-width: 100%;
    height: auto;
    display: block;
}
a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}
nav ul{
    list-style: none;
}
/* ========== 全局容器（页面版心通用） ========== */
button {
    background: transparent;
    border: none;
    cursor: pointer;
    font-family: inherit;
}
/* ========== 全局容器 ========== */
.container {
    width: 100%;
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 40px;
}

/* ========== 顶部信息条 top-bar ========== */
.top-bar {
    background-color: var(--primary-blue);
    color: var(--pure-white);
    font-size: 14px;
    padding: 12px 0;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}
.top-bar-flex {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.top-bar a {
    color: #fff;
}

/* ========== Header PC基础样式 ========== */
header {
    background: var(--pure-white);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.04);
}
.header-flex {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
    max-width: 100%;
    padding: 0 12%;
    margin: 0 auto;
    background: #fff;
}
.logo-area img {
    height: 55px;
    object-fit: contain;
}

/* 主菜单PC横向布局 */
.main-menu {
    display: flex;
    gap: 20px;
    align-items: center;
}
.menu-item {
    position: relative;
}
.menu-row {
    display: flex;
    align-items: center;
    gap: 6px;
}
.menu-link {
    font-size: 16px;
    font-weight: 600;
    color: var(--dark-charcoal);
    padding: 8px 4px;
    letter-spacing: 0.5px;
}
.menu-link:hover,
.menu-link.active {
    color: var(--hover-blue);
    background-color: var(--hover-bg);
    border-bottom: 6px solid var(--hover-blue);
}
.arrow-btn {
    font-size: 12px;
    color: var(--dark-charcoal);
    padding: 4px 6px;
    transition: transform 0.2s ease;
    will-change: transform;
}
/* 箭头旋转动画 */
.menu-item.has-sub.open-desktop .arrow-btn,
.menu-item.has-sub.open-mobile .arrow-btn {
    transform: rotate(180deg) translateZ(0);
}
/* PC端下拉菜单 垂直列 */
.submenu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 180px;
    background: #fff;
    box-shadow: 0 6px 18px rgba(0,0,0,0.08);
    border-radius: 4px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(8px) translateZ(0);
    transition: all 0.2s ease;
    display: flex;
    flex-direction: column;
    z-index: 999;
    will-change: transform, opacity;
}
.submenu li a {
    display: block;
    padding: 12px 20px;
    font-weight: 500;
    white-space: nowrap;
}
.submenu li a:hover {
    background: var(--hover-bg);
    color: var(--hover-blue);
}
/* PC悬浮显示下拉 */
.menu-item.has-sub:hover .submenu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0) translateZ(0);
}

/* ========== 汉堡菜单 PC隐藏 提升z-index防止遮挡 ========== */
.menu-toggle {
    display: none;
    font-size: 28px;
    cursor: pointer;
    color: var(--dark-charcoal);
    padding: 8px;
    flex-shrink: 0;
    z-index: 1001;
    position: relative;
}

/* ========== 移动端768px响应式 ========== */
@media(max-width: 768px) {
    .container {
        padding: 0 20px;
    }
    .header-flex {
        position: relative;
        flex-wrap: wrap;
        flex-direction: row !important;
        justify-content: space-between;
        align-items: center;
        height: auto;
        padding: 15px 12%;
    }
    .menu-toggle {
        display: block;
        order: 2;
    }
    .logo-area {
        order: 1;
    }
    /* 移动端导航容器 */
    header nav#mainNav {
        width: 100%;
        position: absolute;
        left: 0;
        top: 100%;
        background: #fff;
        box-shadow: 0 8px 15px rgba(0,0,0,0.08);
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.25s ease;
        order: 3;
        will-change: max-height;
    }
    header nav#mainNav.open {
        max-height: 1200px;
    }
    /* 主菜单改为垂直单列 */
    .main-menu {
        flex-direction: column;
        padding: 15px 20px;
        gap: 8px !important;
        align-items: stretch;
    }
    .menu-row {
        justify-content: center;
        width: 100%;
    }
    .menu-link {
        padding: 10px 0;
        flex: 1;
        text-align: center;
    }

    /* 移动端下拉菜单 移除css变量，固定动画 */
    .menu-item.has-sub {
        position: static;
    }
    .submenu {
        position: static;
        box-shadow: none;
        background: #f8fafc;
        margin-top: 6px;
        border-left: 3px solid var(--hover-blue);
        min-width: unset;
        max-height: 0;
        overflow: hidden;
        opacity: 1;
        visibility: visible;
        transform: none;
        transition: max-height 0.2s ease;
        will-change: max-height;
    }
    .menu-item.has-sub.open-mobile .submenu {
        max-height: 400px;
    }
    .submenu li a {
        text-align: center;
        padding: 10px 0;
    }

    /* 顶部通栏移动端 */
    .top-bar-flex {
        flex-direction: column;
        text-align: center;
        gap: 15px;
    }
    /* 移动端取消PC悬浮下拉 */
    .menu-item.has-sub:hover .submenu {
        opacity: 0;
        visibility: hidden;
    }
}
/*footer底部样式*/
        /* 页脚样式：完全匹配第二张截图深色布局 */
        /* 页脚样式：完全匹配第二张截图深色布局 */
footer {
    background-color: #2c2f38;
    color: #e2e8f0;
    padding: 50px 0 30px;
}
.footer-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr 1fr;
    gap: 30px;
    margin-bottom: 35px;
}
.footer-contact-item {
    display: flex;
    align-items: flex-start;
    gap:14px;
    margin-bottom:22px;
}
.footer-contact-icon {
    width:50px;
    height:50px;
    border-radius:50%;
    background:#444750;
    display:flex;
    align-items:center;
    justify-content:center;
    flex-shrink:0;
    font-size:24px;
}
.footer-col h5 {
    font-size:22px;
    margin-bottom:20px;
    font-weight:600;
    color:#fff;
}
.footer-col ul {
    list-style:none;
}
.footer-col ul li {
    margin-bottom:10px;
    font-size:16px;
}
.footer-col ul li a:hover {
    color:#8da9c4;
}
.footer-bottom-text {
    text-align:center;
    padding-top:25px;
    border-top:1px solid #444750;
    font-size:17px;
    color:#b0b8c4;
}
.footer-contact-text a{
    font-size:20px;
    font-weight:500;
    color:#fff;
}

/* 响应式适配页脚部分 */
@media(max-width: 1200px) {
    .footer-row { grid-template-columns: repeat(3,1fr); gap:25px; }
}
@media(max-width: 768px) {
    .footer-row { grid-template-columns: 1fr; }
}