/* 重置和基础样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: "Microsoft YaHei", "PingFang SC", -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}

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

/* 头部样式 */
.header {
    background-color: #fff;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
    gap: 20px;
}

.lang-switcher {
    display: flex;
    gap: 8px;
}

.lang-btn {
    padding: 6px 16px;
    background-color: transparent;
    border: 1px solid #ddd;
    color: #666;
    font-size: 13px;
    cursor: pointer;
    border-radius: 4px;
    transition: all 0.3s;
}

.lang-btn:hover {
    border-color: #c41e3a;
    color: #c41e3a;
}

.lang-btn.active {
    background-color: #c41e3a;
    border-color: #c41e3a;
    color: #fff;
}

.logo h1 {
    font-size: 28px;
    color: #1a1a1a;
    font-weight: 700;
    letter-spacing: 2px;
}

.logo-sub {
    font-size: 12px;
    color: #666;
    letter-spacing: 1px;
}

.nav {
    display: flex;
    gap: 40px;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-size: 15px;
    font-weight: 500;
    transition: color 0.3s;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: #c41e3a;
}

.nav-link.active::after {
    content: "";
    position: absolute;
    bottom: -8px;
    left: 0;
    right: 0;
    height: 2px;
    background-color: #c41e3a;
}

/* 主视觉区域 */
.hero {
    margin-top: 80px;
    height: 600px;
    background: url("../images/车间背景.jpg") center/cover no-repeat;
    position: relative;
    display: flex;
    align-items: center;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: #fff;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    letter-spacing: 4px;
}

.hero-subtitle {
    font-size: 18px;
    margin-bottom: 40px;
    opacity: 0.9;
}

.btn-primary {
    display: inline-block;
    padding: 15px 40px;
    background-color: #c41e3a;
    color: #fff;
    text-decoration: none;
    font-size: 16px;
    font-weight: 500;
    letter-spacing: 2px;
    transition: background-color 0.3s, transform 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background-color: #a01828;
    transform: translateY(-2px);
}

/* 通用区块样式 */
.section {
    padding: 100px 0;
}

.section-title {
    font-size: 36px;
    text-align: center;
    margin-bottom: 20px;
    color: #1a1a1a;
    font-weight: 700;
    letter-spacing: 3px;
}

.section-subtitle {
    text-align: center;
    color: #666;
    margin-bottom: 60px;
    font-size: 16px;
}

/* 关于我们 */
.about {
    background-color: #fff;
}

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

.about-text h3 {
    font-size: 28px;
    margin-bottom: 20px;
    color: #1a1a1a;
}

.about-text p {
    font-size: 16px;
    color: #555;
    margin-bottom: 15px;
    line-height: 1.8;
}

.about-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    margin-top: 60px;
}

.feature {
    text-align: center;
    padding: 30px 20px;
    background-color: #f9f9f9;
    border-radius: 8px;
    transition: transform 0.3s, box-shadow 0.3s;
}

.feature:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 48px;
    margin-bottom: 15px;
    display: block;
}

.feature h4 {
    font-size: 18px;
    margin-bottom: 10px;
    color: #1a1a1a;
}

.feature p {
    font-size: 14px;
    color: #666;
}

/* 产品展示 */
.products {
    background-color: #f5f5f5;
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.product-card {
    background-color: #fff;
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

.product-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
}

.product-image {
    height: 250px;
    background-color: #e0e0e0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.product-image.placeholder {
    background: linear-gradient(135deg, #f0f0f0 0%, #e0e0e0 100%);
    color: #999;
    font-size: 14px;
}

.product-title {
    font-size: 18px;
    padding: 20px 20px 10px;
    color: #1a1a1a;
    font-weight: 600;
}

.product-desc {
    font-size: 14px;
    padding: 0 20px 25px;
    color: #666;
}

/* 技术实力 */
.technology {
    background-color: #fff;
}

.tech-content {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.tech-item {
    background-color: #f9f9f9;
    padding: 40px 30px;
    border-radius: 8px;
    border-top: 4px solid #c41e3a;
}

.tech-item h3 {
    font-size: 22px;
    margin-bottom: 25px;
    color: #1a1a1a;
    font-weight: 600;
}

.tech-item ul {
    list-style: none;
}

.tech-item li {
    padding: 10px 0;
    color: #555;
    position: relative;
    padding-left: 20px;
}

.tech-item li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 6px;
    height: 6px;
    background-color: #c41e3a;
    border-radius: 50%;
}

/* 联系我们 */
.contact {
    background-color: #1a1a1a;
    color: #fff;
}

.contact .section-title {
    color: #fff;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 30px;
}

.contact-item {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.contact-icon {
    font-size: 32px;
    flex-shrink: 0;
}

.contact-item h4 {
    font-size: 16px;
    margin-bottom: 8px;
    color: #fff;
    font-weight: 600;
}

.contact-item p {
    color: #aaa;
    font-size: 15px;
}

.contact-form {
    background-color: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: 8px;
}

.form-input,
.form-textarea {
    width: 100%;
    padding: 15px;
    margin-bottom: 20px;
    background-color: rgba(255, 255, 255, 0.1);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: #fff;
    font-size: 15px;
    border-radius: 4px;
    transition: border-color 0.3s;
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: #888;
}

.form-input:focus,
.form-textarea:focus {
    outline: none;
    border-color: #c41e3a;
}

.form-textarea {
    min-height: 120px;
    resize: vertical;
}

.contact-form .btn-primary {
    width: 100%;
}

/* PDF证书样式 */
.cert-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.cert-item {
    background-color: #fff;
    border: 1px solid #eee;
    border-radius: 8px;
    padding: 15px;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    gap: 12px;
}

.cert-item:hover {
    border-color: #c41e3a;
    box-shadow: 0 4px 12px rgba(196, 30, 58, 0.15);
    transform: translateY(-2px);
}

.cert-icon {
    font-size: 14px;
    font-weight: 600;
    flex-shrink: 0;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 6px;
    color: white;
    background: linear-gradient(135deg, #c41e3a 0%, #8b1428 100%);
}

.cert-info {
    flex: 1;
    min-width: 0;
}

.cert-title {
    font-size: 14px;
    font-weight: 600;
    color: #1a1a1a;
    margin-bottom: 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.cert-link {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    font-size: 12px;
    color: #c41e3a;
    text-decoration: none;
    transition: color 0.3s;
}

.cert-link:hover {
    color: #a01828;
    text-decoration: underline;
}

/* 页脚 */
.footer {
    background-color: #111;
    color: #888;
    padding: 60px 0 30px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid #222;
}

.footer-info h3 {
    color: #fff;
    font-size: 20px;
    margin-bottom: 8px;
}

.footer-info p {
    font-size: 14px;
}

.footer-links {
    display: flex;
    gap: 30px;
}

.footer-links a {
    color: #888;
    text-decoration: none;
    font-size: 14px;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #c41e3a;
}

.footer-bottom {
    text-align: center;
    font-size: 13px;
}

/* 响应式设计 */
@media (max-width: 992px) {
    .nav {
        gap: 20px;
    }

    .hero-title {
        font-size: 36px;
    }

    .about-features {
        grid-template-columns: 1fr 1fr;
    }

    .product-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .tech-content {
        grid-template-columns: 1fr 1fr;
    }

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

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 15px;
    }

    .nav {
        gap: 15px;
        flex-wrap: wrap;
        justify-content: center;
    }

    .nav-link {
        font-size: 14px;
    }

    .hero {
        height: 450px;
    }

    .hero-title {
        font-size: 28px;
    }

    .section {
        padding: 60px 0;
    }

    .section-title {
        font-size: 28px;
    }

    .about-features {
        grid-template-columns: 1fr;
    }

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

    .tech-content {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        gap: 20px;
        text-align: center;
    }

    .footer-links {
        justify-content: center;
        flex-wrap: wrap;
    }
}

/* 视频展示样式 */
.videos {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.video-card {
    background: #fff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.15);
}

.video-wrapper {
    width: 100%;
    aspect-ratio: 16/9;
    background: #000;
    overflow: hidden;
}

.video-player {
    width: 100%;
    height: 100%;
    display: block;
}

.video-title {
    font-size: 18px;
    color: #333;
    margin: 20px 20px 10px;
    font-weight: 600;
}

.video-desc {
    font-size: 14px;
    color: #666;
    margin: 0 20px 25px;
    line-height: 1.6;
}

@media (max-width: 1024px) {
    .video-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .video-title {
        font-size: 16px;
    }
    
    .video-desc {
        font-size: 13px;
    }
}