/* ============================================================
   枢星数智科技官网 - 全局基础样式
   重写版本 v6.0 - H5全vw单位 / 零媒体查询 / PC+H5 完全统一
   设计稿基准：375px（移动端）
   ============================================================ */

/* ========== 全局重置 ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    font-size: 0.875rem;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color 0.25s ease;
}

a:hover { color: #1a73e8; }

img, video {
    max-width: 100%;
    display: block;
    height: auto;
}

ul, ol { list-style: none; }

button, input, textarea {
    outline: none;
    border: none;
    font-family: inherit;
}

button { cursor: pointer; background: none; }

/* ========== 颜色变量（主色调） ========== */
:root {
    --primary-color: #1a3a5f;
    --secondary-color: #2c5aa0;
    --accent-color: #00c4f3;
    --accent-color1: rgba(0,196,243,0.5);
    --highlight-color: #ff6b35;
    --text-dark: #1a1a1a;
    --text-medium: #4a5568;
    --text-light: #718096;
    --bg-light: #f5f7fa;
    --bg-gray: #fafbfc;
    --border-color: #e2e8f0;
    --white: #ffffff;
    --shadow-sm: 0 0.125rem 0.5rem rgba(0, 0, 0, 0.06);
    --shadow-md: 0 0.25rem 1rem rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 0.5rem 2rem rgba(0, 0, 0, 0.12);
    --gradient-primary: linear-gradient(135deg, #00c4f3 0%, #2c5aa0 100%);
    --gradient-blue: linear-gradient(135deg, #1a73e8 0%, #4dabf7 100%);
    --gradient-accent: linear-gradient(135deg, #1a73e8 0%, #00b4d8 100%);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);

    /* 紧凑间距系统（PC端 rem） */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 2.5rem;

    /* 圆角系统（PC端 rem） */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;

    /* 字号体系（PC端 rem） */
    --fs-xs: 0.75rem;
    --fs-sm: 0.8125rem;
    --fs-base: 0.875rem;
    --fs-md: 0.9375rem;
    --fs-lg: 1rem;
    --fs-xl: 1.125rem;
    --fs-2xl: 1.25rem;
    --fs-3xl: 1.5rem;
    --fs-4xl: 1.75rem;
    --fs-5xl: 2rem;
    --fs-6xl: 2.25rem;
    --fs-7xl: 2.625rem;
}

/* ========== 容器 ========== */
.container {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0 1.25rem;
}

.is-mobile .container { padding: 0 3.2vw; }

/* ========== 顶部导航栏 ========== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 4rem;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(0.625rem);
    -webkit-backdrop-filter: blur(0.625rem);
    box-shadow: 0 1px 0 rgba(0, 0, 0, 0.05);
    z-index: 1000;
    transition: all 0.3s ease;
}

.is-mobile .header { height: 13.87vw; }

.is-home .header,
.header.header-transparent {
    background: transparent;
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    box-shadow: none;
}

.is-home .header .nav-link,
.is-home .header .arrow,
.is-home .header .logo-cn,
.is-home .header .logo-en,
.header.header-transparent .nav-link,
.header.header-transparent .arrow,
.header.header-transparent .logo-cn,
.header.header-transparent .logo-en {
    color: #fff;
    text-shadow: 0 1px 4px rgba(0, 0, 0, 0.35);
}

.is-home .header .menu-toggle span,
.header.header-transparent .menu-toggle span { background: #fff; }

.is-home .header .nav-link::after,
.header.header-transparent .nav-link::after { background: #fff; }

.is-home .header.header-scrolled,
.header.header-scrolled {
    background: rgba(255, 255, 255, 0.99);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.is-home .header.header-scrolled .nav-link,
.is-home .header.header-scrolled .arrow,
.is-home .header.header-scrolled .logo-cn,
.is-home .header.header-scrolled .logo-en,
.header.header-scrolled .nav-link,
.header.header-scrolled .arrow,
.header.header-scrolled .logo-cn,
.header.header-scrolled .logo-en {
    color: var(--text-dark);
    text-shadow: none;
}

.is-home .header.header-scrolled .menu-toggle span,
.header.header-scrolled .menu-toggle span { background: var(--text-dark); }

.is-home .header.header-scrolled .nav-link::after,
.header.header-scrolled .nav-link::after { background: var(--accent-color); }

.is-home .header:has(.nav.h5-mode),
.header.header-transparent:has(.nav.h5-mode) {
    background: rgba(255, 255, 255, 0.99) !important;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08) !important;
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
}

.is-home .header:has(.nav.h5-mode) .menu-toggle span,
.header.header-transparent:has(.nav.h5-mode) .menu-toggle span {
    background: var(--text-dark) !important;
}

.header-inner {
    max-width: 90rem;
    height: 100%;
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.is-mobile .header-inner { padding: 0 3.2vw; }

.logo {
    display: flex;
    align-items: center;
    flex-shrink: 0;
}

.logo-img {
    height: 2.5rem;
    width: auto;
    max-width: 10rem;
    display: block;
    object-fit: contain;
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.is-mobile .logo-img { height: 9.07vw; max-width: 34.67vw; }

.logo:hover .logo-img { opacity: 0.85; }

.logo-img-light { color: #fff; }

.nav {
    display: flex;
    align-items: center;
    height: 100%;
    gap: 0.125rem;
}

.nav-item {
    position: relative;
    height: 100%;
    display: flex;
    align-items: center;
}

.nav-link {
    display: flex;
    align-items: center;
    height: 100%;
    padding: 0 1rem;
    font-size: 0.9375rem;
    color: var(--text-dark);
    font-weight: 500;
    position: relative;
    cursor: pointer;
    transition: color 0.3s ease;
    white-space: nowrap;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 1.25rem;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: width 0.3s ease;
}

.nav-item:hover .nav-link,
.nav-link.active { color: var(--accent-color); }

.nav-item:hover .nav-link::after,
.nav-link.active::after { width: 1.5rem; }

.nav-link .arrow {
    margin-left: 0.25rem;
    font-size: 0.625rem;
    transition: transform 0.3s ease;
}

.nav-item:hover .nav-link .arrow { transform: rotate(180deg); }

.submenu {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%) translateY(0.5rem);
    background: var(--white);
    min-width: 10rem;
    padding: 0.5rem 0;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-md);
    opacity: 0;
    visibility: hidden;
    transition: all 0.25s ease;
    z-index: 100;
    border: 1px solid var(--border-color);
}

.nav-item:hover .submenu {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(0);
}

.submenu-item {
    display: block;
    padding: 0.625rem 1.25rem;
    color: var(--text-dark);
    font-size: 0.875rem;
    white-space: nowrap;
    transition: all 0.2s ease;
    position: relative;
    background: var(--white);
}

.submenu-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 0;
    height: 2px;
    background: var(--accent-color);
    transition: width 0.3s ease;
    z-index: 1;
}

.submenu-item:hover {
    color: var(--accent-color);
    padding-left: 1.75rem;
    background: var(--bg-light);
}

.submenu-item:hover::before { width: 0.625rem; }

.menu-toggle {
    display: none;
    width: 2rem;
    height: 2rem;
    flex-direction: column;
    justify-content: center;
    gap: 0.3125rem;
    cursor: pointer;
}

.is-mobile .menu-toggle { display: flex; width: 5.33vw; height: 5.33vw; gap: 1.33vw; }

.menu-toggle span {
    display: block;
    width: 1.5rem;
    height: 2px;
    background: var(--text-dark);
    transition: all 0.3s ease;
    border-radius: 2px;
}

.is-mobile .menu-toggle span { width: 4vw; }

.menu-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.is-mobile .menu-toggle.active span:nth-child(1) { transform: translateY(1.87vw) rotate(45deg); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }
.is-mobile .menu-toggle.active span:nth-child(3) { transform: translateY(-1.87vw) rotate(-45deg); }

/* ========== 主体内容区 ========== */
.main {
    /* min-height: calc(100vh - 4rem); */
}
/* min-height: calc(100vh - 13.87vw); */
.is-mobile .main { margin-top: 13.87vw;  }

/* ========== 通用区块 - 紧凑 ========== */
.section {
    padding: 3rem 0;
    position: relative;
}

.is-mobile .section { padding: 8vw 0; }

.section-header {
    text-align: center;
    margin-bottom: 1.75rem;
}

.is-mobile .section-header { margin-bottom: 5vw; }

.section-tag {
    display: inline-block;
    font-size: 0.75rem;
    color: var(--accent-color);
    letter-spacing: 3px;
    text-transform: uppercase;
    margin-bottom: 0.625rem;
    position: relative;
    padding: 0 1.125rem;
    font-weight: 500;
}

.is-mobile .section-tag { font-size: 2.93vw; padding: 0 4.8vw; margin-bottom: 2.67vw; letter-spacing: 0.8vw; }

.section-tag::before,
.section-tag::after {
    content: '';
    position: absolute;
    top: 50%;
    width: 1.5rem;
    height: 1px;
    background: var(--accent-color);
}

.is-mobile .section-tag::before,
.is-mobile .section-tag::after { width: 6.4vw; }

.section-tag::before { left: -0.875rem; }
.is-mobile .section-tag::before { left: -3.73vw; }
.section-tag::after { right: -0.875rem; }
.is-mobile .section-tag::after { right: -3.73vw; }

.section-title {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.625rem;
    letter-spacing: 1px;
    line-height: 1.3;
}

.is-mobile .section-title { font-size: 5.87vw; margin-bottom: 2.67vw; }

.section-subtitle {
    font-size: 0.875rem;
    color: var(--text-light);
    max-width: 40rem;
    margin: 0 auto;
    line-height: 1.7;
}

.is-mobile .section-subtitle { font-size: 3.2vw; max-width: 80vw; }

/* ========== 按钮 ========== */
.btn {
    display: inline-block;
    padding: 0.625rem 1.5rem;
    font-size: 0.875rem;
    font-weight: 500;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.is-mobile .btn { padding: 2.67vw 6.4vw; font-size: 3.73vw; }

.btn-primary {
    background: var(--gradient-blue);
    color: white;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.3);
}

.is-mobile .btn-primary { box-shadow: 0 1.07vw 3.2vw rgba(26, 115, 232, 0.3); }

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(26, 115, 232, 0.4);
    color: white;
}

.is-mobile .btn-primary:hover { transform: translateY(-0.53vw); box-shadow: 0 2.13vw 5.33vw rgba(26, 115, 232, 0.4); }

.btn-outline {
    background: transparent;
    color: var(--accent-color);
    border: 1px solid var(--accent-color);
}

.btn-outline:hover {
    background: var(--accent-color);
    color: white;
}

.btn-arrow {
    display: inline-flex;
    align-items: center;
    color: var(--accent-color);
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.3s ease;
    cursor: pointer;
}

.is-mobile .btn-arrow { font-size: 3.73vw; }

.btn-arrow::after {
    content: '→';
    margin-left: 0.375rem;
    transition: transform 0.3s ease;
}

.is-mobile .btn-arrow::after { margin-left: 1.6vw; }

.btn-arrow:hover { color: var(--secondary-color); }
.btn-arrow:hover::after { transform: translateX(4px); }
.is-mobile .btn-arrow:hover::after { transform: translateX(1.07vw); }

/* ========== 入场动画 ========== */
.fade-in {
    opacity: 0;
    transform: translateY(1.25rem);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.is-mobile .fade-in { transform: translateY(3.33vw); }

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.fade-in-left {
    opacity: 0;
    transform: translateX(-1.25rem);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.is-mobile .fade-in-left { transform: translateX(-3.33vw); }

.fade-in-left.visible {
    opacity: 1;
    transform: translateX(0);
}

.fade-in-right {
    opacity: 0;
    transform: translateX(1.25rem);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.is-mobile .fade-in-right { transform: translateX(3.33vw); }

.fade-in-right.visible {
    opacity: 1;
    transform: translateX(0);
}

.fade-in-scale {
    opacity: 0;
    transform: scale(0.95);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in-scale.visible {
    opacity: 1;
    transform: scale(1);
}

.counter {
    display: inline-block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--accent-color);
    line-height: 1;
}

.is-mobile .counter { font-size: 6.4vw; }

/* ========== 卡片通用样式 ========== */
.card {
    background: var(--white);
    border-radius: var(--radius-md);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    transition: all 0.4s ease;
    cursor: pointer;
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.is-mobile .card:hover { transform: translateY(-1.07vw); }

/* ========== 通用页面头部 - 紧凑 ========== */
.page-banner {
    height: 12.5rem;
    background: var(--gradient-primary);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.is-mobile .page-banner { height: 42.67vw; }

.page-banner::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image:
        radial-gradient(circle at 20% 50%, rgba(26, 115, 232, 0.3) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(0, 180, 216, 0.3) 0%, transparent 50%);
}

.page-banner-content {
    position: relative;
    z-index: 1;
    text-align: center;
    animation: fadeInUp 0.8s ease;
}

.page-banner-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: 2px;
}

.is-mobile .page-banner-title { font-size: 6.4vw; margin-bottom: 2vw; letter-spacing: 0.5vw; }

.page-banner-subtitle {
    font-size: 0.8125rem;
    color: rgba(255, 255, 255, 0.8);
    letter-spacing: 1px;
}

.is-mobile .page-banner-subtitle { font-size: 3.2vw; letter-spacing: 0.3vw; }

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(1.25rem); }
    to { opacity: 1; transform: translateY(0); }
}

/* .is-mobile @keyframes fadeInUp {
    from { opacity: 0; transform: translateY(3.33vw); }
    to { opacity: 1; transform: translateY(0); }
} */

/* 动画定义放顶层，不要嵌套在class里 */
@keyframes fadeInUp {
  from { 
    opacity: 0; 
    transform: translateY(3.33vw); 
  }
  to { 
    opacity: 1; 
    transform: translateY(0); 
  }
}

.is-mobile {
  animation: fadeInUp 0.4s ease forwards;
}

.breadcrumb {
    max-width: 80rem;
    margin: 0 auto 0.75rem;
    padding: 0.75rem 1.25rem 0;
    font-size: 0.8125rem;
    color: var(--text-light);
}

.is-mobile .breadcrumb { padding: 2.67vw 3.2vw 0; font-size: 3.2vw; margin-bottom: 2vw; }

.breadcrumb a { color: var(--text-light); }
.breadcrumb a:hover { color: var(--accent-color); }
.breadcrumb-separator { margin: 0 0.5rem; color: var(--text-light); }
.is-mobile .breadcrumb-separator { margin: 0 1.33vw; }
.breadcrumb-current { color: var(--accent-color); }

/* ========== 页脚 - 紧凑 ========== */
.footer {
    background: #0d1b2a;
    color: rgba(255, 255, 255, 0.6);
    padding: 2.5rem 0 0;
}

.is-mobile .footer { padding: 6.67vw 0 0; }

.footer-grid {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0 1.25rem;
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
    gap: 2rem;
    padding-bottom: 1.5rem;
}

.is-mobile .footer-grid {
    grid-template-columns: 1fr;
    gap: 5.33vw;
    padding: 0 3.2vw 5vw;
}

.footer-col h4 {
    color: white;
    font-size: 0.9375rem;
    margin-bottom: 0.875rem;
    font-weight: 500;
    position: relative;
    padding-bottom: 0.5rem;
}

.is-mobile .footer-col h4 { font-size: 4vw; margin-bottom: 3.73vw; padding-bottom: 2.67vw; }

.footer-col h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 1.5rem;
    height: 2px;
    background: var(--accent-color);
}

.is-mobile .footer-col h4::after { width: 6.4vw; }

.footer-about {
    font-size: 0.8125rem;
    line-height: 1.7;
    margin-top: 0.75rem;
}

.is-mobile .footer-about { font-size: 3.2vw; margin-top: 3.2vw; }

.footer-links li { margin-bottom: 0.5rem; }
.is-mobile .footer-links li { margin-bottom: 2.13vw; }

.footer-links a {
    font-size: 0.8125rem;
    transition: padding-left 0.3s ease;
    color: rgba(255, 255, 255, 0.6);
}

.is-mobile .footer-links a { font-size: 3.2vw; }

.footer-links a:hover {
    color: var(--accent-color);
    padding-left: 0.25rem;
}

.is-mobile .footer-links a:hover { padding-left: 1.07vw; }

.footer-contact p {
    font-size: 0.8125rem;
    margin-bottom: 0.375rem;
    line-height: 1.6;
}

.is-mobile .footer-contact p { font-size: 3.2vw; margin-bottom: 1.6vw; }

.footer-contact strong {
    color: white;
    margin-right: 0.375rem;
}

.is-mobile .footer-contact strong { margin-right: 1.6vw; }

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: 0.875rem 0;
    text-align: center;
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.4);
}

.is-mobile .footer-bottom { padding: 3.73vw 0; font-size: 2.93vw; }

.footer-bottom a {
    color: rgba(255, 255, 255, 0.4);
    margin: 0 0.5rem;
}

.is-mobile .footer-bottom a { margin: 0 1.33vw; }

.footer-bottom a:hover { color: var(--accent-color); }

/* ========== 返回顶部 ========== */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 2.5rem;
    height: 2.5rem;
    background: var(--gradient-blue);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(1rem);
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.3);
    z-index: 99;
}

.is-mobile .back-to-top {
    bottom: 4.27vw;
    right: 4.27vw;
    width: 9.6vw;
    height: 9.6vw;
    font-size: 4.27vw;
    box-shadow: 0 1.07vw 3.2vw rgba(26, 115, 232, 0.3);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px rgba(26, 115, 232, 0.4);
}

.is-mobile .back-to-top:hover { transform: translateY(-1.07vw); box-shadow: 0 2.13vw 5.33vw rgba(26, 115, 232, 0.4); }

/* ========== 响应式图片/视频工具类 ========== */
.img-cover {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.img-contain {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.video-cover {
    position: absolute;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    transform: translate(-50%, -50%);
    object-fit: cover;
}

/* ========== 工具类 ========== */
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.is-mobile .mt-1 { margin-top: 2.13vw; }
.mt-2 { margin-top: 0.75rem; }
.is-mobile .mt-2 { margin-top: 3.2vw; }
.mt-3 { margin-top: 1rem; }
.is-mobile .mt-3 { margin-top: 4.27vw; }
.mt-4 { margin-top: 1.5rem; }
.is-mobile .mt-4 { margin-top: 6.4vw; }
.mt-5 { margin-top: 2rem; }
.is-mobile .mt-5 { margin-top: 8.53vw; }
.mb-1 { margin-bottom: 0.5rem; }
.is-mobile .mb-1 { margin-bottom: 2.13vw; }
.mb-2 { margin-bottom: 0.75rem; }
.is-mobile .mb-2 { margin-bottom: 3.2vw; }
.mb-3 { margin-bottom: 1rem; }
.is-mobile .mb-3 { margin-bottom: 4.27vw; }
.mb-4 { margin-bottom: 1.5rem; }
.is-mobile .mb-4 { margin-bottom: 6.4vw; }
.mb-5 { margin-bottom: 2rem; }
.is-mobile .mb-5 { margin-bottom: 8.53vw; }

/* ========== H5 导航模式（移动端） ========== */
.nav.h5-mode {
    position: fixed;
    top: 4rem;
    left: 0;
    width: 100%;
    height: calc(100vh - 4rem);
    background: var(--white);
    flex-direction: column;
    align-items: stretch;
    padding: 0;
    overflow-y: auto;
    transform: translateX(100%);
    transition: transform 0.3s ease;
    gap: 0;
    z-index: 999;
}

.is-mobile .nav.h5-mode {
    top: 13.87vw;
    height: calc(100vh - 13.87vw);
}

.nav.h5-mode.open { transform: translateX(0); }

.nav.h5-mode .nav-item {
    height: auto;
    flex-direction: column;
    align-items: stretch;
    border-bottom: 1px solid var(--border-color);
}

.nav.h5-mode .nav-link {
    height: 2.875rem;
    padding: 0 0.875rem;
    width: 100%;
    justify-content: space-between;
    font-size: 0.875rem;
}

.is-mobile .nav.h5-mode .nav-link {
    height: 12.27vw;
    padding: 0 3.73vw;
    font-size: 3.73vw;
}

.nav.h5-mode .nav-link::after { display: none; }

.nav.h5-mode .nav-item.active .arrow { transform: rotate(180deg); }

.nav.h5-mode .submenu {
    position: static;
    transform: none;
    opacity: 1;
    visibility: visible;
    box-shadow: none;
    background: var(--white);
    width: 100%;
    border-top: 0;
    display: none;
    border: none;
    border-radius: 0;
    padding: 0;
}

.nav.h5-mode .nav-item.active .submenu {
    display: block;
    border-top: 1px solid var(--border-color);
}

.nav.h5-mode .submenu-item {
    padding: 0.75rem 2rem;
    color: var(--text-dark) !important;
    background: var(--white) !important;
    font-size: 0.875rem;
    line-height: 1.5;
    display: block !important;
    opacity: 1 !important;
    visibility: visible !important;
    transition: padding-left 0.2s ease, color 0.2s ease, background 0.2s ease;
}

.is-mobile .nav.h5-mode .submenu-item {
    padding: 3.2vw 8.53vw;
    font-size: 3.73vw;
}

.nav.h5-mode .submenu-item:hover,
.nav.h5-mode .submenu-item:active {
    padding-left: 2.5rem;
    color: var(--accent-color);
    background: var(--bg-light) !important;
}

.is-mobile .nav.h5-mode .submenu-item:hover,
.is-mobile .nav.h5-mode .submenu-item:active {
    padding-left: 10.67vw;
}

/* ========== PC端隐藏汉堡菜单、显示完整导航 ========== */
.nav:not(.h5-mode) { display: flex; }
.is-mobile .nav:not(.h5-mode) { display: none; }