.portal-nav {
    height: clamp(80px, 5vw, 140px);
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 2000;
    background-color: transparent;
    transition:
        background-color 0.1s linear,
        backdrop-filter 0.1s linear,
        height 0.4s cubic-bezier(0.4, 0, 0.2, 1),
        box-shadow 0.4s ease;
    display: flex;
    align-items: center;
    will-change: height, background-color;
}

.nav-active-state {
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.05);
}


.portal-nav.nav-active-state {
    background-color: rgba(255, 255, 255, 0.85) !important;
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    box-shadow:
        0 4px 12px rgba(0, 0, 0, 0.08),
        0 1px 2px rgba(0, 0, 0, 0.04);
}

.fluid-container-portal {
    width: 100% !important;
    max-width: none !important;
    padding: 0 8% !important;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    transition: padding 0.4s ease;
}

/* ==========================================================================
   2. Logo 区域 (还原您的原始样式)
   ========================================================================== */
.nav-logo-area {
    width: clamp(160px, 12vw, 360px) !important;
    display: flex;
    align-items: center;
    position: relative;
    z-index: 3000 !important;
}

.logo-svg {
    width: 100%;
    height: auto;
    display: block;
}

.logo-svg path,
.logo-svg text {
    fill: #ffffff;
    transition: fill 0.4s ease;
}

.nav-active-state .logo-svg .cls-2 {
    fill: #25a6b3 !important;
}

.nav-active-state .logo-svg .cls-3 {
    fill: #20aebc !important;
}

.nav-active-state .logo-svg .cls-4 {
    fill: #063f44 !important;
}

.nav-active-state .logo-svg .cls-5 {
    fill: #075e65 !important;
}

.nav-active-state .logo-svg .cls-6 {
    fill: #158791 !important;
}

.svg-main-text {
    font-family: "Alibaba PuHuiTi" !important;
    font-weight: 600;
}

/* 英文：Circular Economy Strategies */
.svg-sub-text {
    font-family: 'Inter' !important;
    font-weight: 500;
    letter-spacing: 0.05em;
}

.nav-active-state .logo-svg .svg-main-text {
    fill: #063f44 !important;
}

.nav-active-state .logo-svg .svg-sub-text {
    fill: #7f7f7f !important;
}

/* ==========================================================================
   3. 语言切换 (还原您的原始样式)
   ========================================================================== */
.lang-switcher-desktop {
    display: flex;
    align-items: center;
    justify-content: center;
}

.lang-item {
    font-weight: 300;
    cursor: pointer;
    display: flex;
    opacity: 0.6;
    align-items: center;
    transition: all 0.3s ease;
    font-size: clamp(0.9rem, 1.1vw, 1.4rem);
    color: rgba(255, 255, 255, 0.9);
    line-height: 1;
}

.nav-active-state .lang-item {
    color: var(--p-blue);
}

.nav-active-state .lang-divider {
    color: rgba(6, 63, 68, 0.3) !important;
}

.lang-item.active {
    color: var(--p-green) !important;
    opacity: 1;
}

.lang-divider {
    /* margin: 0 clamp(8px, 1vw, 20px); */
    padding: 0 2px 0 2px;
    color: rgba(255, 255, 255, 0.3);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1em;
    height: 100%;
}

.lang-item::before {
    content: "";
    display: inline-block;
    /* width: 22px; */
    height: 16px;
    /* margin-right: 8px; */
    background-size: cover;
    background-position: center;
    border-radius: 2px;
}

.lang-zh::before {
    /* background-image: url('/uploads/cn.svg'); */
}

.lang-en::before {
    /* background-image: url('/uploads/us.svg'); */
}

/* ==========================================================================
   4. 桌面端导航菜单 (还原您的原始样式)
   ========================================================================= */
.navbar-collapse-custom {
    flex: 1;
    display: flex;
    justify-content: flex-end;
    padding-right: 50px;
}

.nav-menu {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    align-items: center;
}

.nav-link {
    color: rgba(255, 255, 255, 0.75) !important;
    font-weight: 300;
    margin: 0 clamp(15px, 2.2vw, 65px);
    font-size: clamp(0.95rem, 1.2vw, 1.5rem);
    padding: 10px 0;
    transition: color 0.3s ease;
    text-decoration: none;
    white-space: nowrap;
    position: relative;
}

.nav-active-state .nav-link {
    color: var(--p-blue) !important;
}

.nav-link:hover,
.nav-link.active {
    color: var(--p-green) !important;
}

/* ==========================================================================
   5. 移动端适配 (针对性修复滚动)
   ========================================================================== */
.mobile-toggle {
    display: none;
    background: none;
    border: none;
    position: relative;
    z-index: 3000 !important;
    cursor: pointer;
}

@media (max-width: 991px) {
    .mobile-toggle {
        display: block;
    }

    .mobile-toggle span {
        display: block;
        width: 25px;
        height: 3px;
        background-color: #ffffff;
        margin: 5px 0;
        transition: 0.3s;
    }

    .nav-active-state .mobile-toggle span {
        background-color: var(--p-blue);
    }

    .navbar-collapse-custom {
        position: fixed !important;
        /* 关键修复：从导航栏底部开始，避免顶部露缝 */
        top: 0 !important;
        padding-top: var(--current-nav-h, 100px) !important;
        left: 0 !important;
        width: 100% !important;
        /* 关键修复：高度设为视口 100%，配合 padding-top */
        height: 100vh !important;
        background: rgba(255, 255, 255, 0.98) !important;
        display: flex !important;
        flex-direction: column !important;
        justify-content: flex-start !important;
        opacity: 0;
        visibility: hidden;
        transform: translateY(-10px);
        transition: all 0.3s ease-out;
        z-index: 2500 !important;

        /* 关键修复：开启纵向滚动 */
        overflow-y: auto !important;
        -webkit-overflow-scrolling: touch;
    }

    .navbar-collapse-custom.show {
        opacity: 1 !important;
        visibility: visible !important;
        transform: translateY(0) !important;
    }

    .nav-menu {
        flex-direction: column !important;
        width: 100% !important;
        /* 还原：这里使用您的原始单分割线逻辑，避免双线 */
        border-top: 1px solid rgba(0, 0, 0, 0.06);
    }

    .nav-menu li {
        width: 100% !important;
        border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    }

    .nav-menu li:last-child {
        border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    }

    .nav-link {
        color: var(--p-blue) !important;
        margin: 0 !important;
        padding: 20px 0 !important;
        display: block !important;
        text-align: center;
        width: 100%;
        font-size: 1.1rem;
    }

    .mobile-menu-footer {
        display: flex !important;
        justify-content: center;
        align-items: center;
        padding: 30px 0 !important;
        /* 增加底部留白，方便滚动 */
        width: 100%;
        /*border-top: 1px solid rgba(0,0,0,0.06) !important;*/
    }
}