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

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --accent-color: #3b82f6;
    --text-dark: #1f2937;
    --text-light: #6b7280;
    --bg-light: #f9fafb;
    --bg-white: #ffffff;
    --border-color: #e5e7eb;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-brand h1 {
    font-size: 1.5rem;
    color: var(--primary-color);
    font-weight: 700;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-dark);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--primary-color);
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    transition: all 0.3s ease;
}

/* Hero 区域 */
.hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    text-align: center;
    overflow: hidden;
}

.hero-video-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    overflow: hidden;
}

.hero-video {
    position: absolute;
    top: 50%;
    left: 50%;
    min-width: 100%;
    min-height: 100%;
    width: auto;
    height: auto;
    transform: translate(-50%, -50%);
    object-fit: cover;
    z-index: 0;
}

/* 如果视频不存在，显示背景图片 */
.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-image: url('images/company-entrance.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    z-index: 0;
    display: none;
}

/* 如果视频加载失败，显示背景 */
.hero-video-container:has(.hero-video:not([src])) .hero-background,
.hero-video-container:has(.hero-video[src=""]) .hero-background {
    display: block;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100" height="100" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    padding: 0 20px;
    animation: fadeInUp 1s ease;
}

.hero-title {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    opacity: 0.95;
}

.hero-description {
    font-size: 1.1rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    border: 2px solid transparent;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: transparent;
    color: white;
    border-color: white;
}

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

.btn-block {
    width: 100%;
    text-align: center;
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
    color: white;
    font-size: 1.5rem;
}

/* 通用区块样式 */
.section {
    padding: 80px 0;
}

.section-alt {
    background: linear-gradient(135deg, #f8fafc 0%, #f1f5f9 100%);
    position: relative;
    overflow: hidden;
}

.section-alt::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, rgba(37, 99, 235, 0.05) 0%, transparent 70%);
    border-radius: 50%;
}

.section-alt::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: -5%;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.05) 0%, transparent 70%);
    border-radius: 50%;
}

.section-header {
    text-align: center;
    margin-bottom: 40px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 1rem;
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--text-light);
}

/* 关于我们 */
.about-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0;
    align-items: center;
    max-width: 1000px;
    margin: 0 auto;
}

.about-content-single {
    grid-template-columns: 1fr;
    max-width: 1000px;
    margin: 0 auto;
}

.about-text {
    background: white;
    padding: 35px 45px;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    position: relative;
    overflow: hidden;
}

.about-text::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
}

.about-text h3 {
    font-size: 1.6rem;
    margin-bottom: 1.2rem;
    color: var(--text-dark);
    font-weight: 700;
    position: relative;
    padding-left: 18px;
}

.about-text h3::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 24px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 2px;
}

.about-text p {
    margin-bottom: 1.2rem;
    color: var(--text-light);
    line-height: 1.8;
    font-size: 1rem;
    text-align: justify;
}

.about-text p:last-of-type {
    margin-bottom: 1.8rem;
}

.about-text p strong {
    color: var(--primary-color);
    font-weight: 600;
}

.stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-top: 30px;
    padding-top: 25px;
    border-top: 2px solid rgba(37, 99, 235, 0.1);
}

.stat-item {
    text-align: center;
    padding: 20px 15px;
    background: linear-gradient(135deg, #f8fafc 0%, #ffffff 100%);
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
    transition: all 0.3s ease;
    border: 1px solid rgba(37, 99, 235, 0.1);
    position: relative;
    overflow: hidden;
}

.stat-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), var(--accent-color));
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 16px rgba(37, 99, 235, 0.15);
    border-color: rgba(37, 99, 235, 0.2);
}

.stat-item:hover::before {
    transform: scaleX(1);
}

.stat-number {
    font-size: 2.2rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
    line-height: 1.2;
}

.stat-label {
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 500;
}

.about-image {
    position: relative;
}

.company-image {
    width: 100%;
    height: 400px;
    object-fit: cover;
    border-radius: 10px;
    box-shadow: var(--shadow-lg);
    transition: transform 0.3s ease;
}

.company-image:hover {
    transform: scale(1.02);
}

.image-placeholder {
    width: 100%;
    height: 400px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 5rem;
    box-shadow: var(--shadow-lg);
}

.image-placeholder p {
    color: rgba(255, 255, 255, 0.9);
    font-size: 0.9rem;
    text-align: center;
    max-width: 80%;
    margin-top: 1rem;
}

/* 产品服务 */
.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

/* 认证信息 */
.certifications {
    margin-top: 60px;
    padding-top: 60px;
    border-top: 2px solid var(--border-color);
}

.certifications-title {
    text-align: center;
    font-size: 1.8rem;
    color: var(--text-dark);
    margin-bottom: 40px;
}

.certifications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.cert-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 20px;
    background: white;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.cert-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.cert-item i {
    color: var(--primary-color);
    font-size: 1.5rem;
}

.cert-item span {
    color: var(--text-dark);
    font-weight: 500;
    font-size: 0.95rem;
}

.product-card {
    background: white;
    padding: 40px 30px;
    border-radius: 10px;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
    text-align: center;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.product-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
}

.product-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.product-card p {
    color: var(--text-light);
    margin-bottom: 1.5rem;
    line-height: 1.8;
}

.product-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: gap 0.3s ease;
}

.product-link:hover {
    gap: 1rem;
}

/* 发展历程 */
.timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
    padding: 30px 0;
    z-index: 1;
}

.timeline::before {
    display: none;
}

.timeline-item {
    position: relative;
    margin-bottom: 30px;
    display: flex;
    align-items: flex-start;
    gap: 25px;
    padding-left: 0;
    opacity: 0;
    animation: fadeInLeft 0.6s ease forwards;
}

.timeline-item:nth-child(1) { animation-delay: 0.1s; }
.timeline-item:nth-child(2) { animation-delay: 0.2s; }
.timeline-item:nth-child(3) { animation-delay: 0.3s; }
.timeline-item:nth-child(4) { animation-delay: 0.4s; }
.timeline-item:nth-child(5) { animation-delay: 0.5s; }
.timeline-item:nth-child(6) { animation-delay: 0.6s; }
.timeline-item:nth-child(7) { animation-delay: 0.7s; }

.timeline-item::before {
    display: none;
}

.timeline-item:hover::before {
    display: none;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-year {
    flex: 0 0 100px;
    text-align: center;
    font-size: 1.1rem;
    font-weight: 700;
    color: white;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    padding: 10px 14px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
    position: relative;
    z-index: 2;
    line-height: 1.3;
    transition: all 0.3s ease;
}

.timeline-year:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(37, 99, 235, 0.4);
}

.timeline-content {
    flex: 1;
    background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
    padding: 22px 24px;
    border-radius: 12px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    position: relative;
    transition: all 0.3s ease;
    border: 1px solid rgba(37, 99, 235, 0.1);
}

.timeline-content::before {
    content: '';
    position: absolute;
    left: -8px;
    top: 20px;
    width: 0;
    height: 0;
    border-top: 8px solid transparent;
    border-bottom: 8px solid transparent;
    border-right: 8px solid #f8fafc;
}

.timeline-content:hover {
    transform: translateX(8px);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.15);
    border-color: rgba(37, 99, 235, 0.2);
    background: linear-gradient(135deg, #ffffff 0%, #f1f5f9 100%);
}

.timeline-icon {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.3rem;
    flex-shrink: 0;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.timeline-icon::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: linear-gradient(45deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transform: rotate(45deg);
    transition: all 0.5s ease;
    opacity: 0;
}

.timeline-content:hover .timeline-icon {
    transform: scale(1.1) rotate(5deg);
    box-shadow: 0 6px 16px rgba(37, 99, 235, 0.4);
}

.timeline-content:hover .timeline-icon::before {
    opacity: 1;
    animation: shine 0.5s ease;
}

.timeline-text {
    flex: 1;
}

.timeline-content h3 {
    font-size: 1.25rem;
    color: var(--text-dark);
    margin-bottom: 10px;
    margin-top: 0;
    font-weight: 600;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.timeline-content p {
    color: var(--text-light);
    line-height: 1.7;
    margin: 0;
    font-size: 0.95rem;
}

/* 我们的优势 */
.advantages-content {
    margin-top: 40px;
}

.advantage-main {
    margin-bottom: 40px;
}

.advantage-card {
    background: white;
    padding: 35px;
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border: 1px solid rgba(37, 99, 235, 0.1);
}

.advantage-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 24px rgba(37, 99, 235, 0.15);
    border-color: rgba(37, 99, 235, 0.2);
}

.advantage-card.highlight {
    background: linear-gradient(135deg, #ffffff 0%, #f8fafc 100%);
    border: 2px solid var(--primary-color);
    box-shadow: 0 6px 20px rgba(37, 99, 235, 0.15);
}

.advantage-card.highlight:hover {
    box-shadow: 0 10px 30px rgba(37, 99, 235, 0.2);
}

.advantage-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    margin-bottom: 20px;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3);
}

.advantage-card h3 {
    font-size: 1.5rem;
    color: var(--text-dark);
    margin-bottom: 15px;
    font-weight: 600;
}

.advantage-card.highlight h3 {
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: 1.8rem;
}

.advantage-card p {
    color: var(--text-light);
    line-height: 1.8;
    font-size: 1rem;
    margin: 0;
}

.advantage-card p strong {
    color: var(--primary-color);
    font-weight: 600;
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

/* 荣誉证书 */
.certificates-showcase {
    margin-top: 40px;
    display: flex;
    justify-content: center;
    align-items: center;
}

.certificate-main-image {
    position: relative;
    max-width: 1200px;
    width: 100%;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
    background: white;
    padding: 20px;
}

.certificate-img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 8px;
}

/* 新闻动态 */
.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.news-card {
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

.news-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.news-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
}

.news-image .image-placeholder {
    height: 100%;
    font-size: 3rem;
}

.news-content {
    padding: 25px;
}

.news-date {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.news-content h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--text-dark);
}

.news-content p {
    color: var(--text-light);
    margin-bottom: 1rem;
    line-height: 1.8;
}

.news-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    transition: gap 0.3s ease;
}

.news-link:hover {
    gap: 1rem;
}

/* 联系我们 */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-item {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
}

.contact-icon {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.contact-details h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-dark);
}

.contact-details p {
    color: var(--text-light);
}

.contact-form {
    background: white;
    padding: 40px;
    border-radius: 10px;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 20px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid var(--border-color);
    border-radius: 8px;
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    resize: vertical;
}

/* 页脚 */
.footer {
    background: var(--text-dark);
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: white;
}

.social-links {
    display: flex;
    gap: 15px;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
}

/* 动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    40% {
        transform: translateX(-50%) translateY(-10px);
    }
    60% {
        transform: translateX(-50%) translateY(-5px);
    }
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes shine {
    0% {
        transform: translateX(-100%) translateY(-100%) rotate(45deg);
    }
    100% {
        transform: translateX(100%) translateY(100%) rotate(45deg);
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: white;
        width: 100%;
        text-align: center;
        transition: left 0.3s ease;
        box-shadow: var(--shadow);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hero-video {
        min-width: 100%;
        min-height: 100%;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .section-title {
        font-size: 2rem;
    }

    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
    }

    .about-text {
        padding: 28px 25px;
    }

    .about-text h3 {
        font-size: 1.4rem;
        margin-bottom: 1rem;
        padding-left: 15px;
    }

    .about-text h3::before {
        width: 3px;
        height: 22px;
    }

    .about-text p {
        font-size: 0.95rem;
        line-height: 1.7;
        margin-bottom: 1rem;
    }

    .about-text p:last-of-type {
        margin-bottom: 1.5rem;
    }

    .stats {
        grid-template-columns: repeat(2, 1fr);
        gap: 15px;
        margin-top: 25px;
        padding-top: 20px;
    }

    .stat-item {
        padding: 18px 12px;
    }

    .stat-number {
        font-size: 1.8rem;
    }

    .certifications-grid {
        grid-template-columns: 1fr;
    }

    .products-grid,
    .news-grid {
        grid-template-columns: 1fr;
    }

    .advantages-grid {
        grid-template-columns: 1fr;
    }

    .advantage-card {
        padding: 25px;
    }

    .advantage-card.highlight h3 {
        font-size: 1.5rem;
    }

    .certificate-main-image {
        padding: 15px;
    }

    .modal-content {
        max-width: 98%;
        padding: 10px;
    }

    .modal-close {
        top: -30px;
        font-size: 30px;
    }

    /* 时间线响应式 */
    .timeline::before {
        left: 50px;
    }

    .timeline-item {
        flex-direction: row !important;
        padding-left: 0;
    }

    .timeline-item::before {
        display: none;
    }

    .timeline-year {
        flex: 0 0 80px;
        font-size: 0.95rem;
        padding: 8px 12px;
    }

    .timeline-content {
        width: 100%;
        padding: 18px;
    }

    .timeline-content::before {
        display: none;
    }

    .timeline-icon {
        width: 45px;
        height: 45px;
        font-size: 1.1rem;
    }

    .timeline-content h3 {
        font-size: 1.15rem;
    }

    .timeline-content p {
        font-size: 0.9rem;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .section {
        padding: 60px 0;
    }

    .contact-form {
        padding: 25px;
    }

    .about-text {
        padding: 25px 20px;
    }

    .about-text h3 {
        font-size: 1.4rem;
        margin-bottom: 1.5rem;
    }

    .about-text p {
        font-size: 0.95rem;
        margin-bottom: 1.5rem;
    }

    .stats {
        grid-template-columns: 1fr;
        gap: 15px;
    }

    .stat-number {
        font-size: 2rem;
    }
}