/* 新增样式 - 2025年3月29日 */
    :root {
        --primary-color: #ff6a00;
        --secondary-color: #2c3e50;
        --accent-color: #3498db;
        --text-color: #333;
        --light-gray: #f5f5f5;
        --border-color: #ddd;
        --dalon-primary: #004078;     /* 蓝色 - 主色调 */
        --dalon-secondary: #f2a900;   /* 黄色 - 辅助色调 */
        --dalon-gray: #373737;        /* 深灰色 - 文本及背景 */
        --dalon-light: #f5f5f5;       /* 浅灰色 - 背景 */
        
        /* 字体系统 */
        --font-primary: 'Segoe UI', -apple-system, BlinkMacSystemFont, Roboto, 'Helvetica Neue', Arial, sans-serif;
        --font-size-base: 16px;
        --font-size-sm: 0.875rem;
        --font-size-lg: 1.125rem;
        --font-size-xl: 1.25rem;
        --font-size-xxl: 1.5rem;
        --line-height-base: 1.6;
        --font-weight-normal: 400;
        --font-weight-medium: 500;
        --font-weight-bold: 600;
        --letter-spacing-base: 0.5px;
    }
  
    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box;
    }
  
    body {
        font-family: var(--font-primary);
        font-size: var(--font-size-base);
        line-height: var(--line-height-base);
        color: var(--dalon-gray);
        background-color: var(--dalon-light);
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
    }
  
    h1, h2, h3, h4, h5, h6 {
        font-family: var(--font-primary);
        line-height: 1.3;
        margin-bottom: 1rem;
    }
  
    h1 {
        font-size: var(--font-size-xxl);
        font-weight: var(--font-weight-normal);
        letter-spacing: var(--letter-spacing-base);
    }
  
    h2 {
        font-size: var(--font-size-xl);
        font-weight: var(--font-weight-medium);
    }
  
    h3 {
        font-size: var(--font-size-lg);
        font-weight: var(--font-weight-medium);
    }
  
    .container {
        max-width: 1440px;
        margin: 0 auto;
        padding: 0 20px;
    }
    .hero-banner {
        background: linear-gradient(135deg, var(--dalon-primary) 0%, #005694 100%);
        color: white;
        position: relative;
        overflow: hidden;
        box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    }
    
    .hero-banner h1 {
        font-weight: 300;
        letter-spacing: 1px;
        margin-bottom: 0.75rem;
    }
    
    .hero-banner p {
        margin: 0 auto;
        opacity: 0.9;
        margin-bottom: 0.75rem;
    }
    
/* 卡片头部颜色 */
.filter-header {
    background-color: #004078;
}

.muffler-header {
    background-color: #004D40;
}

.bushing-header {
    background-color: #00695C;
}

.other-header {
    background-color: #546E7A;
}

    /* Header Styles */
    .top-header {
        background: var(--secondary-color);
        color: white;
        padding: 8px 0;
        font-size: 14px;
    }
  
    .top-header .container {
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
  
    .contact-info {
        display: flex;
        gap: 20px;
    }
  
    .contact-info span {
        transition: color 0.3s;
        cursor: pointer;
    }
  
    .contact-info span:hover {
        color: var(--primary-color);
    }
  
    .language-selector {
        display: flex;
        align-items: center;
        gap: 8px;
    }
  
    .language-selector a {
        color: inherit;
        text-decoration: none;
        transition: color 0.3s;
    }
  
    .language-selector a:hover {
        color: var(--primary-color);
    }
  
    .main-header {
        padding: 20px 0;
        background: white;
        box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    }
  
    .main-header .container {
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
  
    .logo img {
        max-height: 60px;
    }
  
    .nav-menu {
        display: flex;
        gap: 30px;
    }
  
    .nav-menu a {
        color: var(--text-color);
        text-decoration: none;
        font-weight: 500;
        transition: color 0.3s;
    }
  
    .nav-menu a:hover {
        color: var(--primary-color);
    }
  
    .quality-badge {
        display: inline-block;
        background-color: var(--dalon-secondary);
        color: var(--dalon-gray);
        padding: 0.25rem 1rem;
        border-radius: 30px;
        font-weight: var(--font-weight-medium);
        font-size: var(--font-size-sm);
        text-transform: uppercase;
        letter-spacing: var(--letter-spacing-base);
    }
    
    .card {
        border: none;
        border-radius: 0;
        transition: transform 0.3s, box-shadow 0.3s;
        margin-bottom: 30px;
    }
    
    .card:hover {
        transform: translateY(-5px);
        box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    }
    
    .card-header {
        border-radius: 0;
        font-weight: 500;
        letter-spacing: 0.5px;
        border: none;
        padding: 1rem 1.5rem;
    }
    
    .card-icon {
        width: 60px;
        height: 60px;
        border-radius: 50%;
        object-fit: cover;
        border: 2px solid #f8f9fa;
        box-shadow: 0 4px 8px rgba(0,0,0,0.1);
        transition: all 0.3s;
    }
    
    .product-link {
        display: flex;
        align-items: center;
        padding: 12px 15px;
        border-left: 3px solid transparent;
        transition: all 0.2s;
        margin-bottom: 10px;
        background-color: white;
    }
    
    .product-link:hover {
        border-left: 3px solid var(--dalon-secondary);
        background-color: rgba(242, 169, 0, 0.05);
    }
    
    .product-link:hover .card-icon {
        border-color: var(--dalon-secondary);
    }
    
    .product-link span {
        font-weight: var(--font-weight-medium);
        color: var(--dalon-gray);
        font-size: var(--font-size-base);
    }
    
    .product-category-title {
        text-transform: uppercase;
        letter-spacing: var(--letter-spacing-base);
        font-size: var(--font-size-sm);
        font-weight: var(--font-weight-bold);
        color: white;
    }
    .products-area {
        background-color: var(--dalon-light);
    }
    
    .advantages-area {
        background-color: white;
    }
    
    .cta-area {
        background-color: var(--dalon-primary);
    }
    
    /* 间距调整 */
    .py-4 {
        padding-top: 1.5rem !important;
        padding-bottom: 1.5rem !important;
    }
    
    .mb-4 {
        margin-bottom: 1.5rem !important;
    }
  
    .btn {
        display: inline-block;
        padding: 12px 30px;
        border-radius: 5px;
        text-decoration: none;
        font-weight: 600;
        transition: all 0.3s;
        cursor: pointer;
    }
  
    .btn-primary {
        background: var(--primary-color);
        color: white;
    }
  
    .btn-primary:hover {
        background: #ff8533;
        transform: translateY(-2px);
    }
  
    .btn-secondary {
        background: white;
        color: var(--primary-color);
    }
  
    .btn-secondary:hover {
        background: #f5f5f5;
        transform: translateY(-2px);
    }
  

  
    /* Footer Styles */
    footer {
        background: var(--secondary-color);
        color: white;
        padding: 8px 0;
    }
  
    .footer-container {
        display: flex;
        justify-content: space-between;
        align-items: center;
        font-size: 14px;
    }
  
    .footer-left {
        display: flex;
        align-items: center;
        gap: 10px;
    }
  
    .footer-right {
        display: flex;
        align-items: center;
        gap: 10px;
    }
  
    .footer-right a {
        color: inherit;
        text-decoration: none;
        transition: color 0.3s;
    }
  
    .footer-right a:hover {
        color: var(--primary-color);
    }
  
    .footer-divider {
        margin: 0 8px;
        color: rgba(255,255,255,0.5);
    }
  

  
    /* Error Message Styles */
    .error-message {
        background: #fff3f3;
        color: #dc3545;
        padding: 15px;
        border-radius: 5px;
        margin: 20px 0;
        text-align: center;
    }
  
    /* Responsive Design */
    @media (max-width: 768px) {
        .nav-menu {
            display: none;
        }
  
        .hero h1 {
            font-size: 36px;
        }
  
        .hero p {
            font-size: 18px;
        }
  
        .cta-buttons {
            flex-direction: column;
        }
  
        .feature-card,
        .product-card {
            margin-bottom: 20px;
        }
  
        .footer-container {
            flex-direction: column;
            gap: 15px;
            padding: 15px 0;
        }
  
        .footer-right {
            flex-wrap: wrap;
            justify-content: center;
        }
  
        .contact-info {
            flex-direction: column;
            gap: 5px;
        }
  
        .language-selector {
            display: none;
        }
  
        .product-actions {
            flex-direction: column;
            gap: 10px;
            align-items: stretch;
        }
        
        .category-tag {
            text-align: center;
        }
        
        .product-actions .btn {
            margin-left: 0;
            text-align: center;
        }
    }
  
    /* Header 样式更新 */
    .header-left {
        display: flex;
        align-items: center;
        gap: 20px;
    }
  
    .menu-btn {
        display: flex;
        align-items: center;
        gap: 8px;
        background: none;
        border: none;
        cursor: pointer;
        padding: 8px;
        color: var(--secondary-color);
        font-size: 16px;
        transition: color 0.3s;
        -webkit-tap-highlight-color: transparent;
        user-select: none;
        -webkit-user-select: none;
    }
  
    .menu-btn:hover {
        color: var(--primary-color);
    }
  
    .menu-icon {
        font-size: 20px;
    }
  
    .menu-text {
        font-weight: 500;
        letter-spacing: 1px;
    }
  
    /* 侧边菜单样式 */
    .side-menu-wrapper {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        z-index: 9999;
        visibility: hidden;
        -webkit-transform: translateZ(0);
        transform: translateZ(0);
        will-change: visibility;
    }
  
    .side-menu-wrapper.active {
        visibility: visible;
    }
  
    .side-menu {
        position: fixed;
        top: 0;
        left: -320px;
        width: 320px;
        height: 100%;
        background: rgba(44, 62, 80, 0.95);
        box-shadow: 2px 0 10px rgba(0,0,0,0.1);
        transition: transform 0.3s ease-out;
        -webkit-transition: -webkit-transform 0.3s ease-out;
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
        z-index: 2;
        will-change: transform;
        backface-visibility: hidden;
        -webkit-backface-visibility: hidden;
    }
  
    .side-menu-wrapper.active .side-menu {
        transform: translateX(320px);
        -webkit-transform: translateX(320px);
    }
  
    .side-menu-overlay {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0,0,0,0.5);
        opacity: 0;
        transition: opacity 0.3s ease-out;
        -webkit-transition: opacity 0.3s ease-out;
        z-index: 1;
        will-change: opacity;
        pointer-events: none;
    }
  
    .side-menu-wrapper.active .side-menu-overlay {
        opacity: 1;
        pointer-events: auto;
    }
  
    .side-menu-header {
        padding: 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        display: flex;
        justify-content: flex-end;
    }
  
    .close-menu {
        background: none;
        border: none;
        font-size: 24px;
        cursor: pointer;
        color: #fff;
        padding: 5px;
        transition: color 0.3s;
    }
  
    .close-menu:hover {
        color: var(--primary-color);
    }
  
    .side-menu-content {
        padding: 20px;
    }
  
    .menu-list {
        list-style: none;
        padding: 0;
        margin: 0;
    }
  
    .menu-item {
        margin-bottom: 0 !important;
        border-bottom: 1px solid rgba(255, 255, 255, 0.05) !important;
    }
  
    .menu-item:last-child {
        border-bottom: none !important;
    }
  
    .menu-link {
        display: flex;
        justify-content: space-between;
        align-items: center;
        color: #fff;
        text-decoration: none;
        font-size: 16px;
        padding: 15px 10px !important;
        transition: all 0.3s ease;
    }
  
    .menu-link:hover {
        color: var(--primary-color);
        background-color: rgba(255, 255, 255, 0.05);
    }
  
    .submenu {
        list-style: none;
        padding: 0;
        margin: 0;
        background: transparent;
        border-radius: 0;
        border-left: none;
        display: block !important;
        padding-left: 15px;
    }
  
    .submenu li {
        border-bottom: 1px solid rgba(255, 255, 255, 0.1);
        margin: 0;
    }
  
    .submenu li:last-child {
        border-bottom: none;
    }
  
    .submenu a {
        color: rgba(255, 255, 255, 0.8);
        text-decoration: none;
        padding: 12px 15px 12px 15px;
        display: block;
        font-size: 14px;
        transition: all 0.3s;
        position: relative;
    }
  
    .submenu a:before {
        content: '';
        position: absolute;
        left: 0;
        top: 50%;
        transform: translateY(-50%);
        width: 4px;
        height: 4px;
        border-radius: 50%;
        background-color: rgba(255, 255, 255, 0.3);
        transition: background-color 0.3s, transform 0.2s;
    }
  
    .submenu a:hover {
        color: var(--primary-color);
        background: rgba(255, 255, 255, 0.05);
        padding-left: 20px;
    }
  
    .submenu a:hover:before {
        background-color: var(--primary-color);
        transform: translateY(-50%) scale(1.2);
    }
  
    .has-submenu > .menu-link {
        color: #fff;
        font-weight: 600;
        text-transform: uppercase;
        letter-spacing: 1px;
        font-size: 14px;
        padding: 15px 0 15px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.15) !important;
        background-color: transparent;
        display: block;
        padding-left: 10px;
        position: relative;
    }
  
    .has-submenu > .menu-link:after {
        content: none;
    }
  
    /* 禁止滚动类 */
    .no-scroll {
        overflow: hidden !important;
        width: 100%;
        position: fixed;
        overscroll-behavior: none;
        -ms-scroll-chaining: none;
    }
  
    /* 响应式调整 */
    @media (max-width: 768px) {
        .menu-btn {
            padding: 5px;
        }
        
        .menu-text {
            display: none;
        }
        
        .side-menu {
            width: 280px;
            left: -280px;
        }
        
        .side-menu-wrapper.active .side-menu {
            transform: translateX(280px);
        }
    }
  
    /* 优化滚动条样式 */
    .side-menu::-webkit-scrollbar {
        width: 6px;
    }
  
    .side-menu::-webkit-scrollbar-track {
        background: rgba(255, 255, 255, 0.1);
    }
  
    .side-menu::-webkit-scrollbar-thumb {
        background: rgba(255, 255, 255, 0.2);
        border-radius: 3px;
    }
  
    .side-menu::-webkit-scrollbar-thumb:hover {
        background: rgba(255, 255, 255, 0.3);
    }
   /* 返回顶部按钮样式 */
   #topBtn {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: var(--secondary-color);
    border: none;
    opacity: 0.8;
    transition: all 0.3s;
    border-radius: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 1000;
    color: white;
  }

  #topBtn:hover {
    opacity: 1;
  }

  #topBtn svg {
    transition: transform 0.3s;
  }

  #topBtn:hover svg {
    transform: translateY(-2px);
  }

  /* 响应式字体调整 */
  @media (max-width: 768px) {
    :root {
        --font-size-base: 15px;
        --font-size-xxl: 1.35rem;
        --font-size-xl: 1.15rem;
        --font-size-lg: 1rem;
    }
    
    .product-category-title {
        font-size: 0.8rem;
    }
    
    .quality-badge {
        font-size: 0.75rem;
    }
  }