/* =============================================
   公用CSS文件 - common.css
   包含：全局样式重置、header、footer、通用组件
   适用于：所有页面的公共部分
   YCW
   ============================================= */

/* =============================================
   全局CSS变量定义
   ============================================= */
:root {
    /* 品牌色系 */
    --brand-primary: #0066CC;
    --brand-light: #4A9EFF;
    --brand-lighter: #2B8BFF;
    --brand-lightest: #5AAFFF;
    
    /* 品牌色透明度变体 */
    --brand-alpha-08: rgba(0, 102, 204, 0.08);
    --brand-alpha-15: rgba(0, 102, 204, 0.15);
    --brand-alpha-25: rgba(0, 102, 204, 0.25);
    
    /* 品牌色渐变 */
    --brand-gradient: linear-gradient(90deg, var(--brand-primary) 0%, var(--brand-light) 100%);
    --brand-gradient-hover: linear-gradient(90deg, var(--brand-lighter) 0%, var(--brand-primary) 100%);
    --brand-gradient-135: linear-gradient(135deg, var(--brand-primary) 0%, var(--brand-lighter) 100%);
    --brand-gradient-180: linear-gradient(180deg, var(--brand-light) 0%, var(--brand-primary) 100%);
}

/* =============================================
   全局样式重置与基础设置
   ============================================= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Microsoft YaHei', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    margin: 0 auto;
    padding: 0 10%;
    box-sizing: border-box;
}

/*响应式设计*/
@media (max-width: 1200px) {
    .container {
        padding: 0 5%;
    }
}

@media (max-width: 800px) {
    .container {
        padding: 0 3%;
    }
}

/* =============================================
   Header 头部导航样式
   ============================================= */
.header {
    background-color: #ffffff;
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    position: relative;
    z-index: 1000;
    transition: all 0.2s ease;
}

.header .container {
    display: flex;
    align-items: center;
    height: 72px;
}

/* Logo区域 */
.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo a {
    line-height: 0%;
}

.logo-img {
    height: 36px;
    border-radius: 4px;
}

.logo-text {
    font-size: 22px;
    font-weight: 600;
    color: #1a1a1a;
    letter-spacing: -0.02em;
}

/* 主导航菜单 */
.nav {
    margin-left: 48px;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 40px;
}

.nav-item {
    position: relative;
}

.nav-link {
    display: flex;
    align-items: center;
    padding: 24px 0;
    text-decoration: none;
    color: #1a1a1a;
    font-size: 15px;
    font-weight: 500;
    letter-spacing: -0.01em;
    transition: color 0.2s ease;
}

.nav-link:hover {
    color: var(--brand-primary);
}

/* 下拉箭头 */
.arrow-down {
    margin-left: 6px;
    font-style: normal;
    opacity: 0.6;
    transition: opacity 0.2s ease, transform 0.2s ease;
}

.arrow-down::before {
    content: '▼';
    font-size: 9px;
    color: currentColor;
}

.nav-item:hover .arrow-down {
    opacity: 1;
    transform: translateY(1px);
}

/* 下拉菜单样式 */
.dropdown-menu {
    position: fixed;
    top: 72px;
    left: 0;
    right: 0;
    width: 80%;
    margin: 0 auto;
    background-color: #ffffff;
    border: 1px solid rgba(0, 0, 0, 0.06);
    border-top: none;
    border-radius: 0 0 12px 12px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all 0.2s ease;
    z-index: 1001;
    backdrop-filter: blur(20px);
}

/* 背景模糊效果 */
.blur-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.02);
    backdrop-filter: blur(2px);
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s ease;
}

.blur-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* 页面模糊状态 */
body.dropdown-open .main {
    filter: blur(3px);
    transition: filter 0.3s ease;
}

body.dropdown-open .header {
    position: relative;
    z-index: 1002;
}

/* 简单二级下拉菜单样式 */
.simple-dropdown-list {
    list-style: none;
    margin: 0;
    padding: 16px 0;
    min-width: 220px;
}

.simple-dropdown-list li a {
    display: block;
    padding: 12px 24px;
    color: #1a1a1a;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
}

.simple-dropdown-list li a:hover {
    background: rgba(0, 114, 206, 0.08);
    color: var(--brand-primary);
}

/* 卡片式下拉菜单样式 */
.promo-dropdown .promo-container {
    padding: 32px 40px;
}

.promo-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 24px;
    color: #1a1a1a;
}

.promo-title a {
    text-decoration: none;
    color: #1a1a1a;
    display: inline-flex;
    align-items: center;
    transition: color 0.2s ease;
}

.promo-title a:hover {
    color: var(--brand-primary);
}

.arrow-right {
    font-style: normal;
    margin-left: 8px;
}

.arrow-right::before {
    content: '>';
    font-size: 16px;
    font-weight: bold;
}

.promo-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 28px;
    justify-items: stretch;
}

.promo-item a {
    display: block;
    padding: 20px;
    border: none;
    border-radius: 8px;
    text-decoration: none;
    color: #1a1a1a;
    transition: all 0.2s ease;
    height: 100%;
    background: transparent;
}

.promo-item a:hover {
    background: rgb(125 180 240 / 5%);
    color: var(--brand-primary);
    transform: translateY(-1px);
}

.promo-item h4 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 8px;
    color: #1a1a1a;
}

.promo-item a:hover h4 {
    color: var(--brand-primary);
}

.promo-item p {
    font-size: 13px;
    color: #666666;
    line-height: 1.5;
}

/* 产品中心下拉菜单特殊样式 */
.dropdown-menu.product-center-dropdown {
    overflow: hidden;
}

.product-center-dropdown .product-dropdown-container {
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding: 32px 40px;
    min-height: 320px;
    box-sizing: border-box;
}

.product-center-dropdown .product-dropdown-body {
    display: flex;
    width: 100%;
    min-width: 0;
}

.product-center-dropdown .product-categories {
    width: 200px;
    flex-shrink: 0;
    padding-right: 24px;
    margin-right: 24px;
    border-right: 1px solid #e9ecef;
}

.product-center-dropdown .category-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.product-center-dropdown .category-item a {
    display: inline-block;
    padding: 8px 0;
    color: #374151;
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    position: relative;
    transition: color 0.2s ease, font-weight 0.2s ease;
    border-bottom: none;
}

.product-center-dropdown .category-item a::after {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    height: 2px;
    background: #111827;
    transform: scaleX(0);
    transform-origin: left;
    transition: none;
}

.product-center-dropdown .category-item:hover a::after,
.product-center-dropdown .category-item.active a::after {
    transform: scaleX(1);
    transform-origin: left;
    transition: transform 250ms ease;
}

.product-center-dropdown .category-item:hover a,
.product-center-dropdown .category-item.active a {
    color: #111827;
    font-weight: 600;
}

.product-center-dropdown .product-details {
    flex: 1;
    position: relative;
    padding: 0;
    min-width: 0;
}

.product-center-dropdown .product-category-content {
    position: static;
    width: 100%;
    box-sizing: border-box;
    display: none;
}

.product-center-dropdown .product-category-content.active {
    display: block;
}

.product-center-dropdown .product-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    width: 100%;
    box-sizing: border-box;
}

.product-center-dropdown .product-card {
    padding: 0;
    background: transparent;
    box-shadow: none;
    text-align: left;
    align-items: flex-start;
    padding-left: 0 !important;
}

.product-center-dropdown .product-card:hover {
    box-shadow: none !important;
    transform: none !important;
}

.product-center-dropdown .product-header h4 {
    font-size: 14px;
    font-weight: 600;
    color: #374151;
    margin: 0 0 6px 0;
    text-align: left;
}

.product-center-dropdown .product-header h4 a {
    color: #374151;
    text-decoration: none;
}

.product-center-dropdown .product-series-name {
    display: block;
    margin: 0 0 12px 0;
    font-size: 12px;
    line-height: 1.4;
    color: #6b7280;
    font-weight: 400;
}

.product-center-dropdown .product-models {
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin: 0 !important;
}

.product-center-dropdown .model-item {
    font-size: 14px;
    color: #4b5563;
    text-decoration: none;
    transition: color 0.2s ease;
    word-break: break-all;
}

.product-center-dropdown .model-item:hover {
    color: var(--brand-primary);
}

/* Header 右侧联系方式 CTA */
.contact-cta {
    margin-left: auto;
    display: flex;
    align-items: center;
}

.contact-btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    height: 40px;
    padding: 0 14px 0 10px;
    border-radius: 999px;
    background: var(--brand-gradient);
    color: #FFF;
    text-decoration: none;
    font-weight: 700;
    font-size: 14px;
    transition: transform .15s ease, box-shadow .2s ease, background .2s ease;
}

.contact-btn:hover {
    transform: translateY(-1px);
    background: var(--brand-gradient-hover);
    box-shadow: 0 10px 28px rgba(0,114,206,0.28);
}

.phone-icon {
    width: 26px;
    height: 26px;
    border-radius: 13px;
    background: #FFF;
    color: var(--brand-primary);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-style: normal;
    font-weight: 900;
}

.phone-icon::before {
    content: "☎";
    font-size: 14px;
    line-height: 1;
}

.contact-text {
    white-space: nowrap;
}

/* =============================================
   Footer 底部样式
   ============================================= */
:root {
    --footer-bg: #0b1220;
    --footer-card-bg: #0f172a;
    --footer-text: #cbd5e1;
    --footer-muted: #94a3b8;
    --footer-border: rgba(148, 163, 184, 0.15);
    --footer-accent: #2dd4bf;
    --footer-link-text: #e2e8f0;
}

.site-footer {
    background: radial-gradient(1200px 600px at 80% -200px, rgba(45, 212, 191, 0.06), transparent 60%),
                radial-gradient(1000px 500px at 10% -150px, rgba(56, 189, 248, 0.06), transparent 60%),
                var(--footer-bg);
    color: var(--footer-text);
    border-top: 1px solid var(--footer-border);
}

.footer-inner {
    margin: 0 auto;
    padding: 48px 10% 16px;
    box-sizing: border-box;
}

.footer-top {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr 1.2fr;
    gap: 24px;
}

.footer-brand {
    background: none;
    border: none;
    border-radius: 0;
    padding: 0;
}

.footer-brand .brand-title {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 600;
}

.footer-brand .brand-title-logo {
    height: 60px;
    width: auto;
    object-fit: contain;
    display: block;
}

.footer-col h4 {
    font-size: 15px;
    font-weight: 600;
    margin: 4px 0 12px;
    color: #e2e8f0;
}

.footer-links,
.footer-contacts {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-links li a {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--footer-text);
    text-decoration: none;
    padding: 6px 0;
    font-size: 14px;
    transition: color .2s ease;
}

.footer-links li a i {
    display: inline-block;
    width: 14px;
    height: 14px;
    border: 1px solid var(--footer-border);
    border-radius: 4px;
}

.footer-links li a:hover {
    color: #ffffff;
}

.footer-contacts li {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 6px 0;
    color: var(--footer-text);
    font-size: 14px;
}

.footer-contacts li strong {
    color: #ffffff;
    font-size: 22px;
    font-weight: 800;
}

.footer-contacts a[href^="mailto:"] {
    color: var(--footer-link-text);
    text-decoration: none;
    transition: color .2s ease;
}

.footer-contacts a[href^="mailto:"]:hover {
    color: #ffffff;
    text-decoration: underline;
}

.footer-contacts .badge {
    font-size: 11px;
    color: var(--footer-accent);
    background: rgba(45, 212, 191, 0.08);
    border: 1px solid rgba(45, 212, 191, 0.3);
    padding: 1px 6px;
    border-radius: 999px;
}

.footer-qrcode {
    display: flex;
    gap: 12px;
    align-items: center;
}

.footer-qrcode .qr-img {
    width: 72px;
    height: 72px;
    border-radius: 10px;
    object-fit: cover;
    background: linear-gradient(180deg, rgba(148,163,184,.12), rgba(148,163,184,.08));
    border: 1px dashed var(--footer-border);
}

.footer-qrcode .qr-text {
    color: var(--footer-muted);
    font-size: 12px;
}

.footer-divider {
    height: 1px;
    background: linear-gradient(to right, transparent, var(--footer-border), transparent);
    margin: 28px 0 12px;
}

.footer-bottom {
    display: flex;
    flex-direction: column;
    gap: 12px;
    color: var(--footer-muted);
    font-size: 12px;
}

.footer-left {
    display: flex;
    align-items: center;
    gap: 10px 16px;
    flex-wrap: wrap;
}

.footer-bottom .compliance {
    line-height: 1.75;
    overflow-wrap: anywhere;
    word-break: break-word;
}

.footer-bottom .legal-links {
    display: flex;
    gap: 16px;
}

.footer-bottom a {
    color: var(--footer-muted);
    text-decoration: none;
}

.footer-bottom a:hover {
    color: #e2e8f0;
}

.police-icon-img {
    width: 16px;
    height: 16px;
    vertical-align: -3px;
    margin-right: 4px;
}

/* =============================================
   通用按钮样式
   ============================================= */
.cs-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 44px;
    padding: 0 24px;
    border-radius: 9999px;
    font-size: 14px;
    font-weight: 800;
    text-decoration: none;
    cursor: pointer;
    transition: all .2s ease;
    border: 1px solid transparent;
    box-shadow: 0 2px 12px rgba(0,114,206,0.09);
}

.cs-btn.primary {
    background: var(--brand-gradient);
    color: #fff;
    border: none;
}

.cs-btn.primary:hover {
    background: var(--brand-gradient-hover);
    transform: translateY(-1px);
    box-shadow: 0 8px 24px rgba(0,114,206,0.15);
}

.cs-btn.ghost {
    background: #FFF;
    color: var(--brand-primary);
    border: 1px solid var(--brand-alpha-25);
    box-shadow: none;
}

.cs-btn.ghost:hover {
    background: #fff;
    color: var(--brand-primary);
    transform: translateY(-1px);
    box-shadow: 0 8px 24px rgba(0,114,206,0.15);
}

/* =============================================
   通用英雄区样式
   ============================================= */
.hero {
    margin-top: 0;
    background: url(../images/banner1.jpg) center / cover no-repeat;
}

.hero .container {
    padding-top: 60px;
    padding-bottom: 60px;
}

.hero-content {
    text-align: left;
}

/* 英雄区标题统一样式 - 提高优先级确保不被其他样式覆盖 */
h1.hero-title, h2.hero-title, h3.hero-title {
    font-size: 36px;
    color: #333;
    margin-bottom: 20px;
}

h1.section-title, h2.section-title, h3.section-title {
    font-size: 36px;
    color: #333;
    margin-bottom: 20px;
}

/* 英雄区标题小屏样式 */
@media (max-width: 768px) {
    h1.hero-title, h2.hero-title, h3.hero-title {
        font-size: 26px;
        color: #333;
        margin-bottom: 10px;
    }
    
    h1.section-title, h2.section-title, h3.section-title {
        font-size: 26px;
        color: #333;
        margin-bottom: 10px;
    }
}

/* SEO友好的隐藏文本样式 - 对搜索引擎可见但用户不可见 */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
    border: 0;
}

/* =============================================
   通用卡片样式
   ============================================= */
.card {
    background: #FFF;
    border: 1px solid #eef2f6;
    border-radius: 12px;
    padding: 20px;
    text-align: left;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

.card:hover {
    box-shadow: 0 8px 32px rgba(24, 144, 255, 0.13);
    transform: translateY(-2px);
}

/* 卡片变体 */
.card.compact {
    padding: 16px;
}

.card.large {
    padding: 24px;
}

.card.center {
    text-align: center;
}

/* =============================================
   通用section容器样式
   ============================================= */
.section {
    padding: 32px 0;
}

.section.large {
    padding: 48px 0;
}

.section.small {
    padding: 24px 0;
}

/* 主要内容区域 */
.main {
    padding: 60px 0;
    text-align: center;
}

/* 限制全局H1样式作用范围，避免影响英雄区和内容页标题 */
.main h1:not(.hero-title):not(.article-title):not(.title) {
    font-size: 36px;
    color: #333;
    margin-bottom: 20px;
}

.main p {
    font-size: 18px;
    color: #666;
    max-width: 600px;
    margin: 0 auto;
}
/* 覆盖 .main p 全局边距对英雄区副标题的影响 */
.main .hero-subtitle {
    margin-left: 0;
    margin-right: 0;
    max-width: 100%;
}

/* =============================================
   通用页面主容器样式
   ============================================= */
.page-main {
    padding-top: 0;
}

/* =============================================
   通用卡片样式
   ============================================= */
.card {
    background: #4A9EFF;
    border: 1px solid #eef2f6;
    border-radius: 12px;
    padding: 16px;
    transition: border-color .2s ease, box-shadow .2s ease, transform .2s ease;
}

.card:hover {
    border-color: #e1ecf8;
    box-shadow: 0 2px 10px rgba(17,24,39,.06);
    transform: translateY(-1px);
}

@media (min-width: 768px) {
    .card {
        padding: 20px;
    }
}

/* =============================================
   通用按钮链接样式
   ============================================= */
.btn-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 32px;
    padding: 0 12px;
    border-radius: 999px;
    border: 1px solid #e6eef7;
    background: #4A9EFF;
    color: #374151;
    text-decoration: none;
    font-size: 14px;
    line-height: 1;
    transition: color .2s ease, border-color .2s ease, background-color .2s ease;
}

.btn-link:hover {
    background: #f5faff;
    border-color: #b7d3f5;
    color: var(--brand-primary);
}

/* =============================================
   通用文本链接下划线动画
   ============================================= */
.link-underline {
    color: inherit;
    text-decoration: none;
    background-image: linear-gradient(currentColor, currentColor);
    background-position: 0 100%;
    background-repeat: no-repeat;
    background-size: 0 1px;
    transition: color .2s ease, background-size .2s ease;
}

.link-underline:hover {
    color: var(--brand-primary);
    background-size: 100% 1px;
}

/* =============================================
   通用Meta信息样式
   ============================================= */
.meta-info {
    font-size: 13px;
    color: #6b7280;
    display: flex;
    align-items: center;
    gap: 6px;
    flex-wrap: wrap;
}

.meta-info .dot {
    color: #9ca3af;
}

/* =============================================
   响应式设计
   ============================================= */
@media (max-width: 1024px) {
    .nav-list {
        gap: 20px;
    }
    
    .dropdown-menu {
        min-width: 600px;
    }
}

@media (max-width: 900px) {
    .hero .container {
        padding-top: 40px;
        padding-bottom: 40px;
    }
}

@media (max-width: 768px) {
    .nav {
        margin-left: 0;
        margin-top: 15px;
    }
    
    .nav-list {
        flex-wrap: wrap;
        gap: 15px;
        justify-content: center;
    }
    
    .dropdown-menu {
        position: fixed;
        left: 0;
        right: 0;
        min-width: auto;
        margin: 0 20px;
        width: 100%;
    }
    
    .promo-grid {
        grid-template-columns: repeat(1, 1fr);
        gap: 16px;
    }
    
    .footer-top {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 1200px) {
    .promo-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 20px;
    }
}

/* =============================================
   移动端导航菜单样式
   ============================================= */

/* 移动端菜单按钮 */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    width: 40px;
    height: 40px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    border-radius: 6px;
    transition: background-color 0.2s;
    position: relative;
    z-index: 1001;
}

.mobile-menu-toggle:hover {
    background-color: rgba(24, 144, 255, 0.1);
}

.hamburger-line {
    width: 24px;
    height: 2px;
    background-color: #333;
    margin: 2px 0;
    transition: all 0.3s ease;
    border-radius: 1px;
}

.mobile-menu-toggle.active .hamburger-line:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.active .hamburger-line:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active .hamburger-line:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* 移动端菜单覆盖层 - 高级模糊效果 */
.mobile-menu-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(0, 0, 0, 0.4) 0%, rgba(0, 0, 0, 0.6) 100%);
    z-index: 998;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    backdrop-filter: blur(8px);
}

.mobile-menu-overlay.active {
    opacity: 1;
    visibility: visible;
}

/* 移动端菜单 - 从顶部下拉，优雅简约设计 */
.mobile-menu {
    position: fixed;
    top: -100%;
    left: 0;
    width: 100%;
    background: linear-gradient(180deg, #ffffff 0%, #fafbfc 100%);
    z-index: 999;
    transition: all 0.35s cubic-bezier(0.25, 0.8, 0.25, 1);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.12);
    max-height: 100vh;
    overflow-y: auto;
}

.mobile-menu.active {
    top: 0;
}

/* 移动端菜单头部 - 极简设计 */
.mobile-menu-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
}

.mobile-logo-img {
    height: 36px;
    width: auto;
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.1));
}

.mobile-menu-close {
    width: 36px;
    height: 36px;
    background: rgba(71, 85, 105, 0.08);
    border: none;
    cursor: pointer;
    position: relative;
    padding: 0;
    border-radius: 10px;
    transition: all 0.3s ease;
    backdrop-filter: blur(5px);
}

.mobile-menu-close:hover {
    background: rgba(71, 85, 105, 0.15);
    transform: scale(1.05);
}

.close-line {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 20px;
    height: 2px;
    background: linear-gradient(90deg, #666 0%, #888 100%);
    border-radius: 1px;
    transition: all 0.3s ease;
}

.close-line:nth-child(1) {
    transform: translate(-50%, -50%) rotate(45deg);
}

.close-line:nth-child(2) {
    transform: translate(-50%, -50%) rotate(-45deg);
}

/* 移动端导航网格布局 - 优雅设计 */
.mobile-nav-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin: 0;
    padding: 28px 22px;
    list-style: none;
    background: linear-gradient(135deg, #f8fafc 0%, #fff 100%)
}

.mobile-nav-item {
    background: rgba(255, 255, 255, 0.9);
    border-radius: 12px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    overflow: hidden;
    position: relative;
    backdrop-filter: blur(5px);
    box-shadow: 0 4px 16px rgb(182 182 182 / 15%);
}

.mobile-nav-item::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--brand-primary), var(--brand-lighter));
    transform: scaleX(0);
    transition: transform 0.3s ease;
    transform-origin: left;
}

.mobile-nav-item:hover::after {
    transform: scaleX(1);
}

.mobile-nav-item:hover {
    background: rgba(255, 255, 255, 0.95);
    border-color: rgba(24, 144, 255, 0.3);
    box-shadow: 0 4px 16px rgba(24, 144, 255, 0.15);
    transform: translateY(-1px);
}

.mobile-nav-link {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 22px 16px;
    color: #475569;
    text-decoration: none;
    font-size: 15px;
    font-weight: 600;
    transition: all 0.3s ease;
    text-align: center;
    min-height: 68px;
    letter-spacing: 0.3px;
}

.mobile-nav-link:hover {
    color: #333;
}

/* 移动端菜单底部 */
.mobile-menu-footer {
    padding: 24px 22px 28px;
    background: linear-gradient(135deg, #f8fafc 0%, #fff 100%);
}

.mobile-contact-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    width: 100%;
    padding: 16px 24px;
    background: var(--brand-gradient-135);
    color: #FFF;
    text-decoration: none;
    border-radius: 12px;
    font-weight: 600;
    font-size: 15px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 4px 16px rgba(24, 144, 255, 0.25);
    position: relative;
    overflow: hidden;
}

.mobile-contact-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.15), transparent);
    transition: left 0.5s ease;
}

.mobile-contact-btn:hover::before {
    left: 100%;
}

.mobile-contact-btn:hover {
    background: linear-gradient(135deg, #2B8BFF 0%, #5AAFFF 100%);
    box-shadow: 0 6px 20px rgba(0, 114, 206, 0.35);
    transform: translateY(-1px);
}

/* =============================================
   响应式显示控制
   ============================================= */

/* 1200px以下显示移动端菜单按钮，隐藏桌面端导航 */
@media (max-width: 1199px) {
    .mobile-menu-toggle {
        display: flex;
    }
    
    .nav {
        display: none;
    }
    
    .contact-cta {
        display: none;
    }
    .mobile-actions {
        display: none;
    }
    /* 确保header布局在移动端正确 */
    .header .container {
        justify-content: space-between;
    }
    
    .logo {
        flex: 0 0 auto;
    }
}

/* 1200px以上隐藏移动端相关元素 */
@media (min-width: 1200px) {
    .mobile-menu-toggle,
    .mobile-menu,
    .mobile-menu-overlay {
        display: none !important;
    }
}

/* =============================================
   统一响应式断点
   ============================================= */

/* 大屏幕 (1200px+) - 桌面端 */
@media (min-width: 1200px) {
    .card.large {
        padding: 28px;
    }
}

/* 中等屏幕 (768px - 1199px) - 平板端 */
@media (max-width: 1199px) and (min-width: 768px) {
    .card {
        padding: 24px;
    }
}

/* 小屏幕 (767px及以下) - 移动端 */
@media (max-width: 767px) {
    .card {
        padding: 16px;
    }
    
    .section {
        padding: 24px 0;
    }
    
    .promo-grid {
        grid-template-columns: repeat(1, 1fr);
    }
    
    .product-center-dropdown .product-dropdown-container {
        flex-direction: column;
        min-height: auto;
        gap: 12px;
        padding: 16px 20px;
    }
    
    .product-center-dropdown .product-dropdown-body {
        flex-direction: column;
    }
    
    .product-center-dropdown .product-categories {
        width: 100%;
        border-right: none;
        border-bottom: 1px solid #e9ecef;
    }
    
    .product-center-dropdown .category-list {
        display: flex;
        overflow-x: auto;
    }
    
    .product-center-dropdown .category-item {
        flex-shrink: 0;
        border-right: 1px solid #e9ecef;
    }
    
    .product-center-dropdown .category-item:last-child {
        border-right: none;
    }
    
    .footer-top {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .footer-top .footer-col:nth-child(2),
    .footer-top .footer-col:nth-child(3),
    .footer-top .footer-col:nth-child(4) {
        display: none;
    }
}

@media (max-width: 640px) {
    .footer-inner {
        padding: 24px 12px 12px;
    }
    
    .footer-bottom {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    
    .footer-left {
        flex-direction: column;
        align-items: flex-start;
        gap: 8px;
    }
    
    .footer-divider {
        margin: 16px 0;
    }
}

@media (max-width: 600px) {
    .contact-text {
        display: none;
    }
    
    .contact-btn {
        padding: 0 8px;
        gap: 0;
    }
    
    .product-center-dropdown .product-grid {
        grid-template-columns: 1fr;
    }
}

/* =============================================
   侧栏卡片样式 - 通用组件
   适用于：list页面和content页面的右侧侧栏
   ============================================= */

/* 侧栏布局 */
.qalist-section .qalist-layout { 
  display: grid; 
  grid-template-columns: 1fr; 
  gap: 20px; 
  margin-top: 24px; 
  align-items: start; 
}
@media (min-width: 1024px) { 
  .qalist-section .qalist-layout { 
    grid-template-columns: minmax(0, 1fr) 320px; 
    gap: 24px 32px; 
  } 
  .qalist-section .qalist-aside { 
    position: static; 
    top: auto; 
  }
}
.qalist-section .qalist-maincol { 
  min-width: 0; 
}

/* 侧栏卡片基础样式 */
.qalist-section .aside-card { 
  background: #FFF; 
  border: 1px solid #eef2f6; 
  border-radius: 12px; 
  padding: 16px; 
  box-shadow: none; 
  text-align: left; 
}
.qalist-section .aside-card + .aside-card { 
  margin-top: 16px; 
}

/* 侧栏标题样式 */
.qalist-section .aside-title { 
  margin: 0 0 10px; 
  font-size: 16px; 
  font-weight: 700; 
  color: #111827; 
  position: relative; 
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding-left: 14px;
}

/* 标题伪元素基础样式 */
.qalist-section .aside-title::before { 
  content: ""; 
  position: absolute; 
  left: 0; 
  top: 50%;
  transform: translateY(-50%);
  width: 4px; 
  height: 1.2em;
  border-radius: 2px; 
}
.qalist-section .aside-title::after {
  content: "";
  height: 1px;
  width: 60px;
  border-radius: 1px;
}

/* 蓝色风格（默认） */
.qalist-section .aside-title::before {
  background: var(--brand-gradient-180);
}
.qalist-section .aside-title::after {
  background: linear-gradient(90deg, rgba(0,114,206,.35) 0%, rgba(0,114,206,0) 100%);
}

/* 绿色风格（可通过添加 .green-style 类使用） */
.qalist-section .aside-title.green-style::before {
  background: linear-gradient(180deg, #34d399 0%, #059669 100%);
}
.qalist-section .aside-title.green-style::after {
  background: linear-gradient(90deg, rgba(16,185,129,.35) 0%, rgba(16,185,129,0) 100%);
}

/* 相关文章通用样式 */
.related {
  margin-top: 24px;
}

.related .related-title {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding-left: 14px;
  margin: 0 0 10px;
  font-weight: 700;
  font-size: 16px;
  color: #111827;
}

.related .related-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 4px;
  height: 1.2em;
  border-radius: 2px;
  background: var(--brand-gradient-180);
}

.related .related-title::after {
  content: "";
  height: 1px;
  width: 60px;
  border-radius: 1px;
  background: linear-gradient(90deg, rgba(0,114,206,.35) 0%, rgba(0,114,206,0) 100%);
}

.related-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

@media (min-width: 600px) {
  .related-list {
    grid-template-columns: 1fr 1fr;
  }
}

.related-item {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 10px;
  padding: 10px;
  border: 1px solid #eef2f6;
  border-radius: 10px;
  background: #FFF;
  text-decoration: none;
  color: inherit;
}

.related-item:hover {
  background: #f8fbff;
}

.related-thumb {
  width: 100%;
  height: 60px;
  border-radius: 8px;
  object-fit: cover;
  border: 1px solid #eef2f6;
}

.related-item h4 {
  margin: 0 0 6px;
  font-size: 14px;
  color: #111827;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.related-item .meta {
  font-size: 12px;
  color: #6b7280;
}

/* 侧栏列表基础样式 */
.qalist-section .aside-list { 
  list-style: none; 
  padding: 0; 
  margin: 0; 
  display: grid; 
  gap: 8px; 
  text-align: left; 
}
.qalist-section .aside-list a { 
  display: inline-flex; 
  align-items: center; 
  justify-content: flex-start; 
  gap: 8px; 
  color: #374151; 
  text-decoration: none; 
  transition: color .2s ease, background-color .2s ease; 
  padding: 6px 8px; 
  border-radius: 8px; 
}
.qalist-section .aside-list a::before { 
  content: ""; 
}
.qalist-section .aside-list a:hover { 
  color: var(--brand-primary); 
  background: #f5faff; 
}

/* 热门问答：数字徽标序号 */
.qalist-section .hot-qa .aside-list { 
  counter-reset: idx; 
}
.qalist-section .hot-qa .aside-list li { 
  counter-increment: idx; 
}
.qalist-section .hot-qa .aside-list a { 
  gap: 12px; 
  position: relative; 
  padding-left: 48px; 
  line-height: 1.45; 
  display: -webkit-box; 
  -webkit-box-orient: vertical; 
  -webkit-line-clamp: 2; 
  line-clamp: 2; 
  overflow: hidden; 
  word-break: break-word; 
}
.qalist-section .hot-qa .aside-list a::before {
  content: counter(idx);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 999px;
  background: #e8f2ff;
  color: var(--brand-primary);
  font-weight: 700;
  font-size: 13px;
  flex: 0 0 22px;
  margin-right: 0;
  position: absolute;
  left: 12px;
  top: 7px;
}

/* 相关产品：箭头前缀 */
.qalist-section .quick-links .aside-list a::before {
  content: "›";
  color: #9ca3af;
  font-size: 16px;
  line-height: 1;
  width: 14px;
  text-align: center;
  position: absolute;
  left: 8px;
  top: 7px;
}
.qalist-section .quick-links .aside-list a {
  position: relative; 
  padding-left: 26px; 
  line-height: 1.45; 
  display: -webkit-box; 
  -webkit-box-orient: vertical; 
  -webkit-line-clamp: 2; 
  line-clamp: 2; 
  overflow: hidden; 
  word-break: break-word; 
}

/* 联系我们卡片 */
.qalist-section .contact-box { 
  background: #fbfdff; 
  border: 1px dashed #d6e7fb; 
  border-radius: 10px; 
  padding: 12px; 
  text-align: left; 
}
.qalist-section .contact-tip { 
  margin: 0 0 6px; 
  color: #6b7280; 
  font-size: 13px; 
}
.qalist-section .contact-phone { 
  display: inline-block; 
  font-weight: 800; 
  color: var(--brand-primary); 
  font-size: 18px; 
  text-decoration: none; 
  letter-spacing: .5px; 
}
.qalist-section .contact-phone:hover { 
  text-decoration: underline; 
}
.qalist-section .contact-desc { 
  margin: 6px 0 0; 
  color: #6b7280; 
  font-size: 12px; 
}