html,body{
    min-height: 100%;
}
/* ===== 导航栏基础 ===== */
.main-navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid #e5e7eb;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 5.5rem;
}

/* Logo */
.nav-logo a {
    font-size: 1.75rem;
    font-weight: 800;
    color: #111827;
    text-decoration: none;
    letter-spacing: -0.025em;
    transition: color 0.3s;
}

.nav-logo a:hover {
    color: #2563eb;
}

/* PC 端菜单 */
.nav-menu {
    display: none;
}

@media (min-width: 768px) {
    .nav-menu {
        display: block;
    }
    .nav-mobile-btn {
        display: none !important;
    }
}

.nav-menu-list {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 4rem;
    list-style: none !important;
    margin: 0 !important;
    padding: 0 !important;
}

.nav-placeholder {
    padding: 0.75rem 1.5rem;
    color: #9ca3af;
    font-size: 0.95rem;
}

/* 移动端按钮 */
.nav-mobile-btn {
    display: block;
    padding: 0.5rem;
    background: transparent;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: background-color 0.3s;
}

.nav-mobile-btn:hover {
    background: #f3f4f6;
}

.nav-mobile-btn svg {
    width: 1.5rem;
    height: 1.5rem;
    color: #374151;
}

/* 移动端菜单 */
.nav-mobile-menu {
    display: none;
    border-top: 1px solid #e5e7eb;
    padding: 1rem 0;
    background: #ffffff;
}

.nav-mobile-menu.active {
    display: block;
}

.nav-mobile-inner {
    padding: 0 1.5rem;
}

.nav-mobile-inner ul {
    list-style: none !important;
    margin: 0 !important;
    padding: 0 !important;
}

/* ===== 强制重置列表样式 ===== */
.main-navbar ul,
.main-navbar li,
.main-navbar ul li {
    list-style: none !important;
    list-style-type: none !important;
    margin: 0 !important;
    padding: 0 !important;
}

/* ===== 一级菜单项 ===== */
.main-navbar .nav-menu-list > .nav-item {
    position: relative !important;
    display: inline-block !important;
}

.main-navbar .nav-item > a {
    display: inline-flex !important;
    align-items: center !important;
    gap: 0.375rem !important;
    padding: 2rem 1.5rem !important;
    font-size: 1.1rem !important;
    font-weight: 500 !important;
    color: #374151 !important;
    text-decoration: none !important;
    border-radius: 0.75rem !important;
    transition: all 0.3s ease !important;
}

.main-navbar .nav-item > a:hover {
    color: #2563eb !important;
}

.main-navbar .nav-item > a svg {
    width: 16px !important;
    height: 16px !important;
    transition: transform 0.3s ease !important;
}

.main-navbar .nav-item:hover > a svg {
    transform: rotate(180deg) !important;
}

/* ===== 大型展开式下拉菜单 ===== */
.main-navbar .nav-menu-list > .nav-item > .submenu {
    position: absolute !important;
    top: 100% !important;
    left: 0 !important;
    transform: translateX(0) translateY(0.5rem) !important;
    min-width: 550px !important;
    max-width: min(800px, calc(100vw - 24px)) !important;
    padding: 1.25rem !important;
    background: #ffffff !important;
    border-radius: 1rem !important;
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.15), 0 8px 16px -8px rgba(0, 0, 0, 0.1) !important;
    border: 1px solid #e5e7eb !important;
    opacity: 0 !important;
    visibility: hidden !important;
    transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1) !important;
    z-index: 100 !important;
    display: none !important;
    pointer-events: none !important;
    grid-template-columns: repeat(2, 1fr) !important;
    gap: 1.25rem !important;
    list-style: none !important;
    margin: 0 !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu.is-flip-x {
    left: auto !important;
    right: 0 !important;
}

/* 透明桥接区域 - 让 hover 不中断 */
.main-navbar .nav-item > a::after {
    content: '' !important;
    position: absolute !important;
    top: 100% !important;
    left: 0 !important;
    width: 100% !important;
    height: 0.5rem !important;
    background: transparent !important;
}

.main-navbar .nav-menu-list > .nav-item:hover > .submenu {
    opacity: 1 !important;
    visibility: visible !important;
    transform: translateX(0) translateY(0) !important;
    display: grid !important;
    pointer-events: auto !important;
}

/* 子菜单项 */
.submenu .nav-item {
    display: block !important;
    position: relative !important;
}

/* 二级 -> 三级 悬停桥接，避免鼠标经过缝隙时菜单消失 */
.submenu .nav-item::after {
    content: '' !important;
    position: absolute !important;
    top: 0 !important;
    right: -0.5rem !important;
    width: 0.5rem !important;
    height: 100% !important;
    background: transparent !important;
}

.submenu .nav-item > a {
    display: block !important;
    padding: 0.95rem 1rem !important;
    color: #0f172a !important;
    font-size: 1.05rem !important;
    font-weight: 600 !important;
    text-decoration: none !important;
    border-radius: 0.6rem !important;
    transition: color 0.2s ease !important;
}

.submenu .nav-item > a:hover {
    color: #2563eb !important;
    background: transparent !important;
}

.submenu .nav-item > a svg {
    float: right !important;
    width: 14px !important;
    height: 14px !important;
    color: #9ca3af !important;
    transform: rotate(-90deg) !important;
    transition: transform 0.3s ease !important;
    margin-top: 0.125rem !important;
}

.submenu .nav-item:hover > a svg {
    transform: rotate(0deg) !important;
    color: #2563eb !important;
}

/* 三级及更深菜单 - 在大菜单内直接展开展示所有子级 */
.main-navbar .nav-menu-list > .nav-item > .submenu .submenu {
    position: static !important;
    margin: 0.5rem 0 0 0 !important;
    min-width: 0 !important;
    max-width: none !important;
    padding: 0 !important;
    background: transparent !important;
    border-radius: 0 !important;
    box-shadow: none !important;
    border: none !important;
    display: block !important;
    grid-template-columns: 1fr !important;
    gap: 0.25rem !important;
    transform: none !important;
    opacity: 1 !important;
    visibility: visible !important;
    transition: none !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu .nav-item > .submenu.is-flip-x {
    right: auto !important;
    left: auto !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu .nav-item:hover > .submenu {
    display: block !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu .submenu .nav-item {
    display: block !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu .submenu .nav-item > a {
    display: block !important;
    padding: 0.45rem 0.75rem 0.45rem 1.25rem !important;
    font-size: 0.95rem !important;
    font-weight: 400 !important;
    color: #64748b !important;
    text-decoration: none !important;
    transition: color 0.2s ease !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu .submenu .nav-item > a:hover {
    color: #2563eb !important;
    background: transparent !important;
}

.main-navbar .nav-menu-list > .nav-item > .submenu .nav-item > a svg {
    display: none !important;
}

/* ===== 移动端菜单项 ===== */
.nav-mobile-menu .nav-mobile-item {
    display: block !important;
}

.nav-mobile-menu .nav-mobile-item > a {
    display: flex !important;
    justify-content: space-between !important;
    align-items: center !important;
    gap: 0.5rem !important;
    padding: 1rem !important;
    color: #1f2937 !important;
    font-weight: 500 !important;
    text-decoration: none !important;
    border-radius: 0.5rem !important;
    transition: all 0.2s ease !important;
}

.nav-mobile-menu .nav-mobile-item > a:hover {
    color: #2563eb !important;
    background: #f3f4f6 !important;
}

.nav-mobile-menu .nav-mobile-item > a svg {
    width: 16px !important;
    height: 16px !important;
    transition: transform 0.3s ease !important;
}

.nav-mobile-menu .nav-mobile-item.active > a svg {
    transform: rotate(180deg) !important;
}

.nav-mobile-menu .submenu {
    display: none !important;
    padding-left: 1rem !important;
    background: transparent !important;
    box-shadow: none !important;
    border: none !important;
    position: static !important;
    min-width: auto !important;
    opacity: 1 !important;
    visibility: visible !important;
    transform: none !important;
}

.nav-mobile-menu .nav-mobile-item.active > .submenu {
    display: block !important;
}

.nav-mobile-menu .submenu .nav-mobile-item > a {
    padding: 0.75rem 1rem !important;
    font-size: 0.9rem !important;
    font-weight: 400 !important;
    color: #6b7280 !important;
}