* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #0066cc;
    --secondary-color: #0099ff;
    --text-dark: #333;
    --text-light: #666;
    --bg-light: #f5f7fa;
    --white: #fff;
    --border-color: #e1e5eb;
    --hover-color: #0052a3;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    color: var(--text-dark);
    line-height: 1.6;
    background: var(--white);
}

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

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

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

.header-top {
    background: var(--bg-light);
    padding: 8px 0;
    font-size: 13px;
    border-bottom: 1px solid var(--border-color);
}

.header-top .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 10px;
}

.header-top .welcome {
    color: var(--text-light);
}

.header-top .contact-info {
    display: flex;
    align-items: center;
    gap: 20px;
    flex-wrap: wrap;
}

.header-top .contact-info a {
    display: flex;
    align-items: center;
    gap: 5px;
    color: var(--text-light);
    transition: color 0.3s;
}

.header-top .contact-info a:hover {
    color: var(--primary-color);
}

.header-main {
    background: var(--white);
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-main .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 15px;
}

.logo img {
    height: 60px;
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-title {
    font-size: 22px;
    font-weight: bold;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-title .reg-mark {
    font-size: 12px;
    color: var(--text-light);
    font-weight: normal;
}

.logo-subtitle {
    font-size: 13px;
    color: var(--text-light);
    margin-top: 2px;
}

.logo-subtitle::before {
    content: "| ";
}

.nav {
    display: flex;
    gap: 30px;
}

.nav a {
    font-size: 15px;
    color: var(--text-dark);
    padding: 10px 0;
    position: relative;
    transition: color 0.3s;
}

.nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s;
}

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

.nav a:hover::after,
.nav a.active::after {
    width: 100%;
}

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

.mobile-menu-btn span {
    width: 25px;
    height: 3px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: 0.3s;
}

.banner {
    position: relative;
    height: 500px;
    overflow: hidden;
}

.banner-slides {
    height: 100%;
    position: relative;
}

.banner-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    transition: opacity 1s ease-in-out;
}

.banner-slide.active {
    opacity: 1;
}

.banner-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.banner-dots {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
}

.banner-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255,255,255,0.5);
    cursor: pointer;
    transition: all 0.3s;
}

.banner-dot.active {
    background: var(--white);
    transform: scale(1.2);
}

.section {
    padding: 60px 0;
}

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

.section-title h2 {
    font-size: 32px;
    color: var(--text-dark);
    margin-bottom: 10px;
}

.section-title p {
    font-size: 16px;
    color: var(--text-light);
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: var(--primary-color);
    margin: 15px auto 0;
}

.bg-light {
    background: var(--bg-light);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text p {
    margin-bottom: 15px;
    color: var(--text-light);
    text-align: justify;
}

.about-text .highlight {
    color: var(--primary-color);
    font-weight: 500;
}

.about-image {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.about-image img {
    width: 100%;
    height: 350px;
    object-fit: cover;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

.product-card {
    background: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    transition: transform 0.3s, box-shadow 0.3s;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0,0,0,0.15);
}

.product-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.product-card .info {
    padding: 15px;
    text-align: center;
}

.product-card h3 {
    font-size: 15px;
    color: var(--text-dark);
    font-weight: 500;
}

.applications-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.app-item {
    background: var(--white);
    padding: 25px 15px;
    border-radius: 10px;
    text-align: center;
    box-shadow: 0 3px 15px rgba(0,0,0,0.05);
    transition: transform 0.3s, box-shadow 0.3s;
}

.app-item:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 20px rgba(0,0,0,0.1);
}

.app-item .icon {
    width: 50px;
    height: 50px;
    margin: 0 auto 15px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 22px;
}

.app-item h4 {
    font-size: 14px;
    color: var(--text-dark);
    font-weight: 500;
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--white);
    margin-bottom: 15px;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.faq-question {
    padding: 18px 20px;
    background: var(--white);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-weight: 500;
    color: var(--text-dark);
    transition: background 0.3s;
}

.faq-question:hover {
    background: var(--bg-light);
}

.faq-question .arrow {
    transition: transform 0.3s;
}

.faq-item.open .faq-question .arrow {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.4s ease-out;
    background: var(--bg-light);
}

.faq-item.open .faq-answer {
    max-height: 500px;
}

.faq-answer .content {
    padding: 20px;
    color: var(--text-light);
    line-height: 1.8;
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
}

.contact-info-section h3 {
    font-size: 24px;
    margin-bottom: 25px;
    color: var(--text-dark);
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    margin-bottom: 25px;
}

.contact-item .icon {
    width: 45px;
    height: 45px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 18px;
    flex-shrink: 0;
}

.contact-item .details h4 {
    font-size: 16px;
    color: var(--text-dark);
    margin-bottom: 5px;
}

.contact-item .details p {
    color: var(--text-light);
    font-size: 14px;
}

.contact-item .details a {
    color: var(--primary-color);
}

.douyin-section {
    margin-top: 30px;
    padding-top: 30px;
    border-top: 1px solid var(--border-color);
}

.douyin-section h4 {
    font-size: 18px;
    margin-bottom: 20px;
    color: var(--text-dark);
}

.douyin-accounts {
    display: flex;
    gap: 30px;
}

.douyin-accounts img {
    width: 150px;
    height: 150px;
    border-radius: 10px;
    box-shadow: 0 3px 15px rgba(0,0,0,0.1);
}

.contact-form-section {
    background: var(--white);
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 5px 25px rgba(0,0,0,0.08);
}

.contact-form-section h3 {
    font-size: 24px;
    margin-bottom: 25px;
    color: var(--text-dark);
}

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

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: var(--text-dark);
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    font-size: 14px;
    transition: border-color 0.3s;
}

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

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

.btn {
    display: inline-block;
    padding: 12px 30px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    border-radius: 5px;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    border: none;
    transition: transform 0.3s, box-shadow 0.3s;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(0,102,204,0.3);
}

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

.case-card {
    background: var(--white);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0,0,0,0.08);
    transition: transform 0.3s;
}

.case-card:hover {
    transform: translateY(-5px);
}

.case-card img {
    width: 100%;
    height: 220px;
    object-fit: cover;
}

.case-card .info {
    padding: 20px;
}

.case-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: var(--text-dark);
}

.case-card p {
    font-size: 14px;
    color: var(--text-light);
}

.footer {
    background: #1a1a2e;
    color: #999;
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    color: var(--white);
    font-size: 18px;
    margin-bottom: 20px;
}

.footer-section p,
.footer-section a {
    font-size: 14px;
    line-height: 2;
    color: #999;
    display: block;
}

.footer-section a:hover {
    color: var(--secondary-color);
}

.footer-bottom {
    padding-top: 20px;
    border-top: 1px solid #333;
    text-align: center;
    font-size: 13px;
}

.footer-bottom a {
    color: #999;
}

.footer-bottom a:hover {
    color: var(--secondary-color);
}

.mobile-nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.8);
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
}

.mobile-nav.open {
    opacity: 1;
    visibility: visible;
}

.mobile-nav-content {
    position: absolute;
    top: 0;
    right: 0;
    width: 280px;
    height: 100%;
    background: var(--white);
    padding: 60px 20px 20px;
}

.mobile-nav-content a {
    display: block;
    padding: 15px 0;
    font-size: 16px;
    color: var(--text-dark);
    border-bottom: 1px solid var(--border-color);
}

.mobile-nav-close {
    position: absolute;
    top: 15px;
    right: 15px;
    width: 30px;
    height: 30px;
    cursor: pointer;
    font-size: 24px;
}

.page-header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    padding: 80px 0 60px;
    text-align: center;
    color: var(--white);
}

.page-header h1 {
    font-size: 36px;
    margin-bottom: 10px;
}

.page-header p {
    font-size: 16px;
    opacity: 0.9;
}

@media (max-width: 992px) {
    .nav {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .mobile-nav {
        display: block;
    }

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

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

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

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

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

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

    .banner {
        height: 400px;
    }
}

@media (max-width: 768px) {
    .header-top .container {
        justify-content: center;
        text-align: center;
    }

    .header-top .welcome {
        width: 100%;
    }

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

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

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

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

    .section {
        padding: 40px 0;
    }

    .section-title h2 {
        font-size: 26px;
    }

    .banner {
        height: 300px;
    }

    .logo-title {
        font-size: 18px;
    }

    .logo img {
        height: 50px;
    }

    .douyin-accounts {
        flex-direction: column;
    }

    .page-header {
        padding: 50px 0 40px;
    }

    .page-header h1 {
        font-size: 28px;
    }
}

.wechat-qr {
    margin-top: 15px;
}

.wechat-qr img {
    width: 120px;
    height: 120px;
    border-radius: 8px;
    box-shadow: 0 3px 15px rgba(0,0,0,0.1);
}