/* 梓鹤科技官网样式 - 红色主题版本 */

/* CSS变量 */
:root {
    --primary-color: #c41230;
    --secondary-color: #8b0000;
    --accent-color: #c41230;
    --text-dark: #1a1a1a;
    --text-gray: #666666;
    --text-light: #999999;
    --bg-light: #f8f8f8;
    --bg-white: #ffffff;
    --border-color: #e5e5e5;
    --shadow: 0 2px 4px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 4px 12px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

/* 重置样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background: var(--bg-white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
}

/* 容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 10px 28px;
    border-radius: 4px;
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
    cursor: pointer;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
    border: none;
}

.btn-primary:hover {
    background: var(--secondary-color);
}

.btn-secondary {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.btn-secondary:hover {
    background: var(--primary-color);
    color: white;
}

/* 导航栏 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: transparent;
    z-index: 999;
    height: 77px;
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.30);
    pointer-events: none;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 77px;
    gap: 40px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    position: relative;
    z-index: 1;
}

.logo img {
    height: 50px;
    width: auto;
}

.logo-text {
    font-size: 22px;
    font-weight: bold;
    color: var(--primary-color);
    letter-spacing: 2px;
    position: relative;
    z-index: 1;
}

.logo-text span {
    color: #666;
    font-weight: normal;
    font-size: 14px;
    display: block;
    letter-spacing: 1px;
}

.nav {
    display: flex;
    align-items: center;
    gap: 8px;
    position: relative;
    z-index: 1;
}

.nav-item {
    position: relative;
    white-space: nowrap;
}

.nav-item > a {
    font-size: 21px;
    font-weight: 400;
    color: #222;
    padding: 28px 16px;
    transition: var(--transition);
    display: block;
    position: relative;
    z-index: 1;
    letter-spacing: 1px;
}

.nav-item:hover > a {
    color: var(--primary-color);
}

.nav-item > a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 14px;
    right: 14px;
    height: 2px;
    background: var(--primary-color);
    transform: scaleX(0);
    transition: var(--transition);
}

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

.lang-switch {
    display: flex;
    align-items: center;
    gap: 4px;
    margin-left: 12px;
}

.lang-btn {
    font-size: 12px !important;
    padding: 4px 8px !important;
    border-radius: 4px;
    letter-spacing: 0 !important;
    transition: all 0.3s;
}



.lang-btn::after {
    display: none !important;
}

/* 中文版：默认透明黑字 */
body:not(.eng-page) .lang-cn,
body:not(.eng-page) .lang-en {
    background: transparent;
    color: #333;
}

/* 中文版：选中项红底白字 */
body:not(.eng-page) .lang-cn.active,
body:not(.eng-page) .lang-en.active {
    background: var(--primary-color);
    color: #fff;
}

/* 中文版：hover白底红字 */
body:not(.eng-page) .lang-cn:hover,
body:not(.eng-page) .lang-en:hover {
    background: #fff;
    color: var(--primary-color);
}

/* 英文版：默认透明黑字 */
.eng-page .lang-cn,
.eng-page .lang-en {
    background: transparent;
    color: #333;
}

/* 英文版：选中项红底白字 */
.eng-page .lang-cn.active,
.eng-page .lang-en.active {
    background: var(--primary-color);
    color: #fff;
}

/* 英文版：hover白底红字 */
.eng-page .lang-cn:hover,
.eng-page .lang-en:hover {
    background: #fff;
    color: var(--primary-color);
}

.dropdown {
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: white;
    box-shadow: var(--shadow-lg);
    border-radius: 4px;
    min-width: 160px;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.nav-item:hover .dropdown {
    opacity: 1;
    visibility: visible;
}

.dropdown a {
    display: block;
    padding: 10px 18px;
    font-size: 13px;
    color: var(--text-dark);
    transition: var(--transition);
}

.dropdown a:hover {
    background: var(--bg-light);
    color: var(--primary-color);
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 10px;
}

.mobile-menu-btn span {
    width: 22px;
    height: 2px;
    background: var(--text-dark);
    transition: var(--transition);
}

/* Banner视频区 - 满屏 */
.hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.video-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
    outline: none;
    box-shadow: none;
}

.video-container video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border: none;
    outline: none;
    display: block;
}

.video-overlay {
    display: none;
}

.hero-content {
    position: relative;
    z-index: 10;
    text-align: center;
    color: white;
    padding: 0 20px;
}

.hero-content h1 {
    font-size: 42px;
    font-weight: bold;
    margin-bottom: 16px;
    letter-spacing: 4px;
}

.hero-content p {
    font-size: 18px;
    margin-bottom: 32px;
    opacity: 0.95;
    letter-spacing: 2px;
}

.hero-content .btn-primary {
    background: var(--primary-color);
    color: white;
    padding: 14px 36px;
    font-size: 15px;
    letter-spacing: 1px;
}

.hero-content .btn-primary:hover {
    background: var(--secondary-color);
}

/* 核心数据展示 */
.stats-section {
    background: white;
    padding: 50px 0;
    border-bottom: 1px solid var(--border-color);
}

.stats-grid {
    display: flex;
    justify-content: space-around;
    text-align: center;
}

.stat-item {
    padding: 0 30px;
}

.stat-number {
    font-size: 44px;
    font-weight: bold;
    color: var(--primary-color);
}

.stat-unit {
    font-size: 18px;
    color: var(--primary-color);
    margin-left: 2px;
}

.stat-label {
    display: block;
    font-size: 13px;
    color: var(--text-gray);
    margin-top: 6px;
    letter-spacing: 1px;
}

/* 区块标题 */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-subtitle {
    display: block;
    font-size: 13px;
    color: var(--primary-color);
    letter-spacing: 2px;
    margin-bottom: 10px;
}

.section-title {
    font-size: 32px;
    font-weight: bold;
    color: var(--text-dark);
    margin-bottom: 14px;
    letter-spacing: 3px;
}

.section-desc {
    font-size: 15px;
    color: var(--text-gray);
    max-width: 600px;
    margin: 0 auto;
}

/* 为什么选择我们 */
.why-choose-section {
    padding: 80px 0;
    background: var(--bg-light);
}

.why-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.why-card {
    background: white;
    padding: 32px 28px;
    border-radius: 6px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
}

.why-card:hover {
    box-shadow: var(--shadow-lg);
}

.why-card h3 {
    font-size: 17px;
    font-weight: bold;
    color: var(--text-dark);
    margin-bottom: 14px;
}

.why-card p {
    font-size: 14px;
    color: var(--text-gray);
    line-height: 1.8;
}

/* 产品服务 */
.products-section {
    padding: 80px 0;
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 20px;
}

.product-card {
    background: white;
    border: 1px solid var(--border-color);
    padding: 24px 20px;
    border-radius: 6px;
    transition: var(--transition);
    cursor: pointer;
    text-align: left;
}

.product-card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow);
}

.product-card h3 {
    font-size: 16px;
    font-weight: bold;
    color: var(--text-dark);
    margin-bottom: 10px;
}

.product-card p {
    font-size: 13px;
    color: var(--text-gray);
    line-height: 1.6;
    margin-bottom: 12px;
}

.product-link {
    font-size: 13px;
    color: var(--primary-color);
}

/* 关于我们 */
.about-section {
    padding: 80px 0;
    background: var(--bg-light);
}

.about-content {
    max-width: 900px;
    margin: 0 auto;
    text-align: left;
}

.about-text p {
    font-size: 15px;
    color: var(--text-gray);
    line-height: 1.9;
    margin-bottom: 16px;
}

.about-text .btn {
    margin-top: 10px;
}

/* 新闻中心 */
.news-section {
    padding: 80px 0;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.news-card {
    background: white;
    padding: 24px;
    border-radius: 6px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.news-card:hover {
    box-shadow: var(--shadow-lg);
}

.news-date {
    font-size: 12px;
    color: var(--text-light);
    display: block;
    margin-bottom: 10px;
}

.news-card p {
    font-size: 14px;
    color: var(--text-gray);
    line-height: 1.7;
    margin-bottom: 12px;
}

.news-link {
    font-size: 13px;
    color: var(--primary-color);
}

/* 页脚 - 红色纯色背景 */
.footer {
    background: #c41e3a;
    color: white;
    padding: 0;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px 0;
}

/* 全屏导航样式 */
.fullscreen-navigation {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 20px;
    margin-bottom: 40px;
}

.fullscreen-navigation__item h3 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 12px;
    color: white;
}

.fullscreen-navigation__item h3 a {
    color: white;
    text-decoration: none;
}

.fullscreen-navigation__item a {
    display: block;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.75);
    margin-bottom: 8px;
    transition: color 0.3s;
}

.fullscreen-navigation__item a:hover {
    color: white;
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    background: rgba(0,0,0,0.15);
    padding: 24px;
    margin-top: 30px;
}

.footer-bottom__content {
    flex: 1;
}

.footer-contacts {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 16px;
}

.footer-contacts > div {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.85);
}

.footer-contacts img {
    width: 14px;
    height: 14px;
    filter: brightness(0) invert(1);
}

.footer-auth-num {
    font-size: 11px;
    color: rgba(255, 255, 255, 0.6);
}

.footer-qrcode {
    flex-shrink: 0;
    margin-left: 40px;
}

.footer-qrcode img {
    width: 80px;
    height: 80px;
    border-radius: 4px;
}

/* 子页面通用样式 */
.page-header {
    background: linear-gradient(135deg, var(--text-dark), #333);
    padding: 40px 0;
    text-align: center;
    color: white;
}

.page-header h1 {
    font-size: 32px;
    margin-bottom: 10px;
    letter-spacing: 4px;
}

.page-header p {
    font-size: 14px;
    opacity: 0.8;
}

.content-section {
    padding: 70px 0;
}

.content-section:nth-child(even) {
    background: var(--bg-light);
}

/* 响应式设计 */
@media (max-width: 1024px) {
    .why-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .product-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-content {
        padding: 30px 20px 0;
    }
    
    .fullscreen-navigation {
        grid-template-columns: repeat(3, 1fr);
        gap: 16px;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 20px;
    }
    
    .footer-qrcode {
        margin-left: 0;
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 8px;
        box-shadow: var(--shadow);
        gap: 0;
    }
    
    .nav.active {
        display: flex;
    }
    
    .nav-item > a {
        padding: 10px 8px;
        font-size: 16px;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .dropdown {
        position: absolute;
        transform: none;
        box-shadow: none;
        background: var(--bg-light);
        border: none;
        opacity: 1;
        visibility: visible;
        display: none;
        padding-left: 20px;
        width: 100%;
        left: 0;
        box-sizing: border-box;
    }
    
    .dropdown.show {
        display: block;
        position: relative;
    }
    
    .hero-content h1 {
        font-size: 28px;
        letter-spacing: 2px;
    }
    
    .hero-content p {
        font-size: 15px;
    }
    
    .stats-grid {
        flex-wrap: wrap;
    }
    
    .stat-item {
        width: 50%;
        padding: 16px;
    }
    
    .stat-number {
        font-size: 32px;
    }
    
    .why-grid,
    .product-grid,
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        padding: 20px 15px 0;
    }
    
    .fullscreen-navigation {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }
    
    .footer-contacts {
        flex-direction: column;
        gap: 10px;
    }
    
    .section-title {
        font-size: 26px;
    }
}

/* 动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fadeInUp {
    animation: fadeInUp 0.6s ease forwards;
}

/* 平滑滚动 */
html {
    scroll-behavior: smooth;
}

/* 英文页面导航字号缩小 */
.eng-nav .nav-item > a {
    font-size: 16px;
    padding: 28px 12px;
}

.eng-nav .dropdown > a {
    font-size: 16px;
}