/* ===== 变量定义 ===== */
:root {
    --primary: #0056b3;        /* 主色调，用于链接、标题等 */
    --primary-light: #4d8fd6; /* 主色调的亮色变体 */
    --secondary: #00a0e3;     /* 辅助色，用于点缀 */
    --accent: #ff6b00;         /* 强调色，用于按钮、图标等需要突出的元素 */
    --accent-light: #ff8c33;  /* 强调色的亮色变体 */
    --dark: #1a2a4a;           /* 深色，用于文本和背景 */
    --dark-light: #2c3e5e;    /* 深色的亮色变体 */
    --light: #f8f9fa;         /* 浅色，用于背景 */
    --gray: #6c757d;           /* 灰色，用于辅助文本 */
    --light-gray: #e9ecef;     /* 浅灰色，用于边框和分隔线 */
    --transition: all 0.3s ease; /* 通用过渡效果 */
    --shadow: 0 5px 15px rgba(0, 0, 0, 0.1);      /* 标准阴影 */
    --shadow-hover: 0 10px 25px rgba(0, 0, 0, 0.15); /* 悬停时的阴影 */
}

/* ===== 基础与全局样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    overflow-x: hidden; /* 防止水平滚动条出现 */
}

body {
    font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif; /* 字体栈 */
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
}

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

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

.container {
    width: 90%;
    max-width: 1200px; /* 内容最大宽度 */
    margin: 0 auto;
    padding: 0 15px;
}

/* 各个区域的通用标题样式 */
.section-title {
    text-align: center;
    margin-bottom: 50px;
}
.section-title h2 {
    font-size: 2.5rem;
    color: var(--dark);
    position: relative;
    display: inline-block;
    padding-bottom: 15px;
    margin-bottom: 15px;
}
/* 标题下方的装饰性横线 */
.section-title h2:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background-color: var(--accent);
}
.section-title p {
    color: var(--gray);
    font-size: 1.1rem;
    max-width: 700px;
    margin: 0 auto;
}

/* 通用按钮样式 */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 4px;
    font-weight: 500;
    text-align: center;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}
.btn-primary { /* 主按钮 */
    background-color: var(--accent);
    color: white;
    border: 2px solid var(--accent);
}
.btn-primary:hover {
    background-color: var(--accent-light);
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
}
.btn-secondary { /* 次要按钮 */
    background-color: transparent;
    color: white;
    border: 2px solid white;
}
.btn-secondary:hover {
    background-color: rgba(255, 255, 255, 0.1);
    transform: translateY(-3px);
}
.btn-small { /* 小按钮 */
    padding: 8px 20px;
    font-size: 0.9rem;
}

/* ===== 导航栏 ===== */
.navbar {
    background-color: rgba(255, 255, 255, 0.95); /* 半透明背景 */
    position: fixed; /* 固定在顶部 */
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 15px 0;
    transition: var(--transition);
}
/* JS控制的滚动后样式 */
.navbar.scrolled {
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    background-color: rgba(255, 255, 255, 0.98);
}
.navbar-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}
.logo img {
    height: 40px;
    width: auto;
}
.logo-text {
    font-size: 24px;
    font-weight: 700;
    color: var(--dark);
}
.logo-text span {
    color: var(--primary);
}
.nav-links {
    display: flex;
    list-style: none;
    align-items: center;
}
.nav-links li {
    margin: 0 15px;
    position: relative;
}
.nav-links a {
    color: var(--dark);
    font-weight: 500;
    font-size: 16px;
    transition: var(--transition);
}
.nav-links a:hover {
    color: var(--primary);
}
/* 导航链接悬停下划线动画 */
.nav-links a:after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary);
    transition: width 0.3s;
}
.nav-links a:hover:after {
    width: 100%;
}
.mobile-toggle { /* 移动端菜单按钮 */
    display: none;
    font-size: 24px;
    cursor: pointer;
    color: var(--dark);
}

/* ===== 语言切换下拉框 ===== */
.language-switcher {
    margin-left: 20px;
}
.dropdown-language {
    position: relative;
    display: inline-block;
}
.dropdown-toggle {
    background-color: transparent;
    border: 1px solid var(--light-gray);
    color: var(--dark);
    padding: 8px 15px;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    transition: var(--transition);
}
.dropdown-toggle:hover {
    background-color: var(--light-gray);
    border-color: var(--gray);
}
.dropdown-menu {
    display: none; /* 默认隐藏 */
    position: absolute;
    top: 110%; /* 按钮下方显示 */
    right: 0;
    background-color: white;
    box-shadow: var(--shadow);
    border-radius: 4px;
    list-style: none;
    padding: 5px 0;
    margin: 0;
    min-width: 120px;
    z-index: 1001; /* 确保在导航栏之上 */
    overflow: hidden;
}
.dropdown-menu.show { /* JS控制显示 */
    display: block;
}
.dropdown-item {
    background: none;
    border: none;
    width: 100%;
    text-align: left;
    padding: 10px 20px;
    cursor: pointer;
    font-size: 14px;
    color: var(--dark);
    transition: var(--transition);
}
.dropdown-item:hover {
    background-color: var(--light);
    color: var(--primary);
}

/* ===== 头部区域 ===== */
.hero {
    background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('../assets/images/Background.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed; /* 背景图固定，产生视差效果 */
    /* height: 100vh; */
    display: flex;
    align-items: center;
    text-align: center;
    color: white;
    padding-top: 100px;
    min-height: 100vh;
    padding-bottom: 50px;
}
.hero-content {
    max-width: 900px;
    margin: 0 auto;
}
.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
}
.hero p {
    font-size: 1.25rem;
    margin-bottom: 30px;
    max-width: 750px;
    margin-left: auto;
    margin-right: auto;
    opacity: 0.9;
}
.hero-btns {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 30px;
}

/* ===== 头部 - 企业理念 ===== */
.company-values-compact {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin: 40px auto;
    padding: 20px;
    max-width: 900px;
    background-color: rgba(0, 0, 0, 0.3); /* 半透明背景 */
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 8px;
    backdrop-filter: blur(5px); /* 毛玻璃效果 */
    color: white;
}
.value-declaration, .core-values {
    flex: 1;
}
.value-declaration {
    text-align: center;
    border-right: 1px solid rgba(255, 255, 255, 0.2);
    padding-right: 40px;
}
.core-values h3, .value-declaration h3 {
    font-size: 1.2rem;
    color: var(--accent-light);
    margin-bottom: 10px;
}
.slogan {
    font-size: 1.8rem;
    font-weight: bold;
    letter-spacing: 2px;
}
.sub-slogan {
    font-size: 0.9rem;
    opacity: 0.8;
}
.value-quote {
    font-style: italic;
    margin-bottom: 15px;
    opacity: 0.9;
}
.value-list {
    list-style: none;
    padding: 0;
    text-align: left;
    display: inline-block;
}
.value-list li {
    padding: 5px 0;
    font-size: 0.95rem;
}
.value-list li::before {
    content: '✓';
    color: var(--accent);
    margin-right: 8px;
}

/* ===== 关于我们 ===== */
.about {
    padding: 100px 0;
    background-color: var(--light);
}
.about-content {
    display: flex;
    align-items: center;
    gap: 50px;
}
.about-text {
    flex: 1;
}
.about-text h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--primary);
}
.about-text p {
    margin-bottom: 15px;
    color: #555;
}
.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 30px;
}
.stat-item {
    text-align: center;
    padding: 25px 15px;
    background: white;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: var(--transition);
}
.stat-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}
.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 5px;
}
.about-image {
    flex: 1;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}
.about-image img {
    transition: transform 0.5s ease;
}
.about-image:hover img {
    transform: scale(1.05);
}

/* ===== 发展历程 (Timeline) ===== */
.timeline {
    padding: 100px 0;
    background-color: var(--light);
}
.timeline-items {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}
/* 中心时间线 */
.timeline-items::before {
    content: '';
    position: absolute;
    top: 0;
    bottom: 0;
    left: 50%;
    width: 3px;
    background-color: var(--accent);
    transform: translateX(-50%);
}
.timeline-item {
    padding: 10px 40px;
    position: relative;
    width: 50%;
    box-sizing: border-box;
    /* 动画初始状态 */
    opacity: 0;
    transform: translateY(50px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}
/* JS添加此类以触发动画 */
.timeline-item.in-view {
    opacity: 1;
    transform: translateY(0);
}
/* 左侧条目 */
.timeline-item:nth-child(odd) {
    left: 0;
    padding-right: 70px;
    text-align: right;
}
/* 右侧条目 */
.timeline-item:nth-child(even) {
    left: 50%;
    padding-left: 70px;
    text-align: left;
}
/* 时间轴上的圆点 */
.timeline-item::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    background-color: white;
    border: 4px solid var(--accent);
    border-radius: 50%;
    top: 20px;
    z-index: 1;
}
.timeline-item:nth-child(odd)::after {
    right: -10px;
}
.timeline-item:nth-child(even)::after {
    left: -10px;
}
.timeline-content {
    padding: 20px 30px;
    background-color: white;
    border-radius: 8px;
    box-shadow: var(--shadow);
    position: relative;
}
.timeline-date {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary);
    margin-bottom: 10px;
}

/* ===== 行业解决方案 ===== */
.industry-solutions {
    padding: 100px 0;
    background-color: white;
}
.solution-tabs {
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
}
.tab-buttons {
    display: flex;
    background-color: var(--light);
}
.tab-btn {
    flex: 1;
    padding: 15px 20px;
    border: none;
    background: none;
    cursor: pointer;
    font-size: 16px;
    font-weight: 600;
    color: var(--gray);
    transition: var(--transition);
    border-bottom: 3px solid transparent;
}
.tab-btn.active {
    color: var(--primary);
    border-bottom-color: var(--accent);
    background-color: white;
}
.tab-content {
    display: none; /* JS会控制其显示 */
    padding: 30px;
    background-color: white;
}
.solution-detail {
    flex: 1;
}
.solution-detail h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--dark);
}
.solution-detail ul {
    list-style: none;
    margin-bottom: 25px;
}
.solution-detail li {
    padding: 10px 0;
    border-bottom: 1px solid var(--light-gray);
    display: flex;
    align-items: center;
}
.solution-detail li:before {
    content: "◼";
    color: var(--accent);
    margin-right: 10px;
    font-size: 0.8rem;
}
.tech-highlight {
    margin: 25px 0;
}
.tech-highlight h4 {
    margin-bottom: 10px;
    font-size: 1.1rem;
}
.tech-tag {
    display: inline-block;
    background-color: var(--light);
    color: var(--primary);
    padding: 5px 15px;
    border-radius: 20px;
    margin-right: 10px;
    margin-bottom: 10px;
    font-size: 0.9rem;
    font-weight: 500;
}
.solution-image {
    flex: 1;
    border-radius: 8px;
    overflow: hidden;
}
.solution-image img {
    transition: transform 0.5s ease;
}
.solution-image:hover img {
    transform: scale(1.03);
}

/* ===== 设备展示 & 轮播 ===== */
.equipment-showcase {
    padding: 100px 0;
    background-color: var(--light);
}
.equipment-carousel {
    position: relative;
    width: 100%;
    overflow: hidden;
}
.carousel-container {
    display: flex;
}
.carousel-slide {
    min-width: 100%;
    box-sizing: border-box;
    display: none;
}
.carousel-slide.active {
    display: block;
}
.carousel-button {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background-color: rgba(0, 0, 0, 0.5);
    color: white;
    border: none;
    padding: 15px;
    cursor: pointer;
    z-index: 10;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    font-size: 1.2rem;
    transition: background-color 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
}
.carousel-button:hover {
    background-color: rgba(0, 0, 0, 0.8);
}
.carousel-button.prev {
    left: 10px;
}
.carousel-button.next {
    right: 10px;
}
.carousel-indicators {
    display: flex;
    justify-content: center;
    padding: 20px 0;
}
.carousel-indicators .indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: #ccc;
    border: none;
    margin: 0 5px;
    cursor: pointer;
}

.carousel-indicators .indicator.active {
    background: #333;
}
.indicator {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background-color: rgba(255, 255, 255, 0.5);
    border: 1px solid rgba(0, 0, 0, 0.2);
    cursor: pointer;
    transition: background-color 0.3s;
    padding: 0;
}
.indicator.active {
    background-color: white;
}
.dynamic-description {
    text-align: center;
    max-width: 800px;
    margin: -20px auto 40px;
    padding: 10px;
}
.dynamic-description .tech-desc {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary);
    margin-bottom: 5px;
}
.dynamic-description .application-desc {
    font-size: 1rem;
    color: var(--gray);
}
.model-viewer-container {
    display: flex;
    gap: 40px;
    align-items: flex-start;
}

.model-viewer-container model-viewer {
    flex: 1;
    min-width: 0; /* Flexbox缩放问题的关键修复 */
    border-radius: 8px;
    box-shadow: var(--shadow);
    background-color: #333;
}

.device-description {
    flex: 1;
    min-width: 0;
}
.device-description > h3 {
    margin-top: 0;
    font-size: 1.8rem;
    color: var(--dark);
    margin-bottom: 15px;
}
.device-description > h4 {
    margin-top: 0;
    font-size: 1.0rem;
    color: var(--dark);
    margin-bottom: 15px;
}
.tech-features {
    list-style: none;
    margin-bottom: 25px;
}
.tech-features li {
    padding: 10px 0;
    border-bottom: 1px solid var(--light-gray);
    display: flex;
    align-items: center;
}
.tech-features i {
    color: var(--accent);
    margin-right: 10px;
    width: 20px;
    text-align: center;
}
.tech-specs {
    margin: 25px 0;
}
.tech-specs h4 {
    margin-bottom: 15px;
    font-size: 1.2rem;
}
.tech-specs table {
    width: 100%;
    border-collapse: collapse;
}
.tech-specs td {
    padding: 8px 0;
    border-bottom: 1px solid var(--light-gray);
}
.tech-specs td:first-child {
    color: var(--gray);
}


/* ===== 成功案例 ===== */
.projects {
    padding: 100px 0;
    background-color: white;
}
.projects-filter {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 40px;
}
.filter-btn {
    padding: 8px 20px;
    background: var(--light);
    border: none;
    border-radius: 30px;
    cursor: pointer;
    transition: var(--transition);
    font-size: 14px;
    font-weight: 500;
}
.filter-btn.active, .filter-btn:hover {
    background: var(--primary);
    color: white;
}
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}
.project-card {
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    display: block; /* 用于筛选 */
}
.project-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
}
.project-image {
    height: 250px;
    background-size: cover;
    background-position: center;
    position: relative;
}
.project-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 86, 179, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition);
    cursor: pointer;
}
.project-card:hover .project-overlay {
    opacity: 1;
}
.project-overlay h3 {
    color: white;
    font-size: 1.5rem;
}
.project-info {
    padding: 20px;
    background: white;
}
.project-info h3 {
    margin-bottom: 10px;
    color: var(--dark);
    font-size: 1.3rem;
}
.project-category {
    color: var(--accent);
    font-weight: 500;
    margin-bottom: 10px;
    display: block;
    font-size: 0.9rem;
}
.case-link {
    display: inline-flex;
    align-items: center;
    color: var(--primary);
    font-size: 0.9rem;
    margin-top: 10px;
    transition: var(--transition);
}
.case-link i {
    margin-left: 5px;
    font-size: 1.2rem;
}
.case-link:hover {
    color: var(--accent);
}

/* ===== 客户见证 ===== */
.testimonials {
    padding: 80px 0;
    background-color: var(--light);
}
.testimonial-slider {
    max-width: 800px;
    margin: 0 auto;
    background: white;
    padding: 40px;
    border-radius: 8px;
    box-shadow: var(--shadow);
}
.testimonial-item {
    display: flex;
    gap: 30px;
}
.client-logo {
    flex: 0 0 150px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.client-logo img {
    max-width: 100%;
    max-height: 80px;
    width: auto;
    height: auto;
    filter: grayscale(100%);
    opacity: 0.7;
    transition: var(--transition);
}
.testimonial-item:hover .client-logo img {
    filter: grayscale(0);
    opacity: 1;
}
.testimonial-content {
    flex: 1;
}
.testimonial-content p {
    font-size: 1.1rem;
    font-style: italic;
    margin-bottom: 20px;
    color: #555;
    position: relative;
    padding-left: 10px;
}
.testimonial-content p:before {
    content: '"';
    font-size: 3rem;
    color: var(--light-gray);
    position: absolute;
    top: -20px;
    left: -15px;
    z-index: 0;
}
.client-info {
    position: relative;
    z-index: 1;
}
.client-info strong {
    display: block;
    color: var(--dark);
}
.client-info span {
    font-size: 0.9rem;
    color: var(--gray);
}

/* ===== ROI计算器 ===== */
.roi-calculator {
    padding: 80px 0;
    background: var(--primary);
    color: white;
}
.calculator-container {
    display: flex;
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow-hover);
}
.calculator-form {
    flex: 1;
    padding: 40px;
    background-color: var(--dark);
    color: white;
}
.calculator-form h3 {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: white;
}
.form-group {
    margin-bottom: 20px;
}
.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
}
.form-group input {
    width: 100%;
    padding: 12px 15px;
    border: none;
    border-radius: 4px;
    background-color: rgba(255, 255, 255, 0.1);
    color: rgb(0, 0, 0);
    border: 1px solid rgba(255, 255, 255, 0.2);
}
.form-group input:focus {
    outline: none;
    border-color: var(--accent);
}
.calculator-result {
    flex: 1;
    padding: 40px;
    background-color: white;
    color: var(--dark);
}
.calculator-result h4 {
    font-size: 1.5rem;
    margin-bottom: 30px;
    color: var(--primary);
}
.result-item {
    display: flex;
    justify-content: space-between;
    padding: 15px 0;
    border-bottom: 1px solid var(--light-gray);
}
.result-item strong {
    color: var(--accent);
    font-size: 1.2rem;
}
.result-total {
    display: flex;
    justify-content: space-between;
    padding: 20px 0;
    margin-top: 20px;
    border-top: 2px solid var(--primary);
    border-bottom: 2px solid var(--primary);
    font-size: 1.1rem;
}
.result-total strong {
    color: var(--accent);
    font-size: 1.5rem;
}
.disclaimer {
    font-size: 0.8rem;
    color: var(--gray);
    margin-top: 20px;
    text-align: center;
}

/* ===== 联系我们 ===== */
.contact {
    padding: 100px 0;
    background-color: var(--light);
}
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}
.contact-info h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--dark);
    position: relative;
    padding-bottom: 10px;
}
.contact-info h3:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 60px;
    height: 3px;
    background: var(--accent);
}
.contact-info p {
    margin-bottom: 30px;
    color: #555;
}
.contact-details {
    margin-top: 30px;
}
.contact-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 25px;
}
.contact-icon {
    font-size: 1.5rem;
    margin-right: 15px;
    color: var(--accent);
}
.contact-item h4 {
    font-size: 1.1rem;
    margin-bottom: 5px;
    color: var(--dark);
}
.contact-item p {
    margin: 0;
    color: #555;
    font-size: 0.95rem;
}
.contact-form {
    background: white;
    padding: 40px;
    border-radius: 8px;
    box-shadow: var(--shadow);
}
.contact-form h3 {
    font-size: 1.8rem;
    margin-bottom: 30px;
    color: var(--dark);
}
.contact-form .form-group {
    margin-bottom: 20px;
}
.contact-form input,
.contact-form textarea,
.contact-form select {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--light-gray);
    border-radius: 4px;
    font-family: inherit;
    transition: var(--transition);
}
.contact-form input:focus,
.contact-form textarea:focus,
.contact-form select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 86, 179, 0.1);
}
.contact-form textarea {
    min-height: 120px;
    resize: vertical;
}

/* ===== 页脚 ===== */
.footer {
    background: var(--dark);
    color: rgba(255, 255, 255, 0.7);
    padding: 60px 0 30px;
}
.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}
.footer-col h4 {
    color: white;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}
.footer-col h4:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background: var(--accent);
}
.footer-col p {
    margin-bottom: 20px;
    font-size: 0.95rem;
    line-height: 1.6;
}
.footer-links {
    list-style: none;
}
.footer-links li {
    margin-bottom: 10px;
}
.footer-links a {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
    transition: var(--transition);
}
.footer-links a:hover {
    color: white;
    padding-left: 5px;
}
.social-links {
    display: flex;
    gap: 15px;
}
.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border-radius: 50%;
    transition: var(--transition);
}
.social-links a:hover {
    background: var(--accent);
    transform: translateY(-3px);
}
.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}
.footer-bottom p {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.5);
}

/* ===== 模态框 (弹窗) 样式 ===== */
.modal {
    display: none;
    position: fixed;
    z-index: 1050;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
    animation: fadeIn 0.3s ease-out;
}
.modal-content {
    position: relative;
    background-color: #fff;
    margin: 5% auto;
    padding: 0;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    width: 80%;
    max-width: 900px;
    animation: slideIn 0.4s ease-out;
}
.modal-close-btn {
    position: absolute;
    top: 15px;
    right: 25px;
    color: #aaa;
    font-size: 32px;
    font-weight: bold;
    border: none;
    background: none;
    cursor: pointer;
    transition: color 0.3s;
    padding: 0;
    line-height: 1;
}
.modal-close-btn:hover {
    color: #000;
}
.modal-body {
    padding: 30px 40px;
}
.modal-detail-layout {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 40px;
    align-items: flex-start;
}
.modal-image-gallery {
    width: 100%;
}
.modal-main-image {
    width: 100%;
    height: auto;
    border-radius: 8px;
    margin-bottom: 10px;
    border: 1px solid var(--light-gray);
}
.modal-thumb-images {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}
.modal-thumb-images img {
    width: 80px;
    height: 80px;
    object-fit: cover;
    border-radius: 4px;
    cursor: pointer;
    border: 2px solid transparent;
    transition: border-color 0.3s;
}
.modal-thumb-images a .active {
    border-color: var(--primary);
}
.modal-text-content h3 {
    font-size: 2rem;
    color: var(--dark);
    margin-top: 0;
    margin-bottom: 15px;
}
.modal-text-content .category {
    display: inline-block;
    background-color: var(--light-gray);
    color: var(--primary);
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.9rem;
    margin-bottom: 20px;
}
.modal-text-content p {
    color: var(--gray);
    line-height: 1.7;
    margin-bottom: 20px;
}
.modal-tech-specs {
    margin-top: 25px;
}
.modal-tech-specs h4 {
    font-size: 1.2rem;
    margin-bottom: 15px;
}
.modal-tech-specs table {
    width: 100%;
    border-collapse: collapse;
}
.modal-tech-specs td {
    padding: 10px;
    border-bottom: 1px solid var(--light-gray);
    font-size: 0.95rem;
}
.modal-tech-specs td:first-child {
    font-weight: 600;
    color: var(--dark-light);
    width: 120px;
}
.modal-cta-btn {
    margin-top: 30px;
    display: inline-block;
    padding: 12px 30px;
    background-color: var(--accent);
    color: white;
    text-decoration: none;
    border-radius: 4px;
    transition: var(--transition);
}
.modal-cta-btn:hover {
    background-color: var(--accent-light);
    transform: translateY(-2px);
}

/* 视频模态框样式 */
.video-modal-content {
    position: relative;
    width: 90%;
    max-width: 960px;
    margin: 5% auto;
    background: #000;
    border-radius: 8px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}
.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 宽高比 */
    height: 0;
    overflow: hidden;
    border-radius: 8px;
}
.video-container iframe,
.video-container video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

/* 动画效果 */
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes slideIn { from { transform: translateY(-50px); opacity: 0; } to { transform: translateY(0); opacity: 1; } }

/* ===== 响应式设计 ===== */
@media (max-width: 1200px) {
    .solution-tabs .tab-content {
        flex-direction: column;
    }
    .solution-image {
        order: -1;
    }
}
@media (max-width: 992px) {
    .hero h1 { font-size: 2.8rem; }
    .about-content,
    .calculator-container {
        flex-direction: column;
    }
    
    .carousel-button {
    top: 25%;
}

    .model-viewer-container {
        display: block;
        /* flex-direction: column; */
    }
}
@media (max-width: 768px) {
    .mobile-toggle {
        display: block;
    }
    .nav-links {
        position: absolute;
        top: 70px; /* 根据导航栏实际高度调整 */
        left: 0;
        background: white;
        width: 100%;
        flex-direction: column;
        align-items: center;
        padding: 20px 0;
        box-shadow: 0 10px 10px rgba(0, 0, 0, 0.1);
        transform: translateY(-150%);
        transition: transform 0.3s ease-in-out;
    }
    .nav-links.active {
        transform: translateY(0);
    }
    .nav-links li {
        margin: 10px 0;
    }
    .hero h1 { font-size: 2.2rem; }
    .hero p { font-size: 1rem; }
    .hero-btns {
        flex-direction: column;
        gap: 15px;
        align-items: center;
    }
    .hero-btns .btn {
        width: 80%;
        max-width: 300px;
    }
    .company-values-compact {
        flex-direction: column;
        gap: 20px;
        padding: 15px;
    }
    .value-declaration {
        border-right: none;
        padding-right: 0;
        padding-bottom: 20px;
        border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    }
    .about-stats {
        grid-template-columns: 1fr;
    }
    .tab-buttons {
        flex-direction: column;
    }
    .tab-btn {
        border-bottom: none;
        border-left: 3px solid transparent;
    }
    .tab-btn.active {
        border-bottom: none;
        border-left-color: var(--accent);
    }
    .timeline-items::before {
        left: 20px;
    }
    .timeline-item {
        width: 100%;
        left: 0 !important;
        padding-left: 70px;
        padding-right: 20px;
        text-align: left !important;
    }
    .timeline-item::after {
        left: 10px !important;
    }
    .testimonial-item {
        flex-direction: column;
        text-align: center;
    }
    .testimonial-content p:before {
        left: 50%;
        transform: translateX(-50%);
    }
    .modal-detail-layout {
        grid-template-columns: 1fr;
    }
    .modal-content {
        width: 90%;
        margin: 10% auto;
    }
    .modal-body {
        padding: 20px;
    }
}
@media (max-width: 576px) {
    .section-title h2 { font-size: 2rem; }
    .section-title p { font-size: 1rem; }
    .solution-detail h3, .device-description h3, .calculator-form h3, .contact-form h3 {
        font-size: 1.5rem;
    }
    .contact-form {
        padding: 25px;
    }
}