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

:root {
    --primary: #1a2b3c;
    --secondary: #2b7abf;
    --accent: #c0392b;
    --light: #f5f7fa;
    --dark: #0e1a26;
    --text: #2c3e50;
    --text-light: #6b7c8d;
    --white: #fff;
    --shadow: 0 4px 24px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.12);
    --radius: 10px;
    --nav-h: 60px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    line-height: 1.7;
    color: var(--text);
    background: var(--white);
    -webkit-font-smoothing: antialiased;
}

.container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; display: block; }
ul { list-style: none; }

/* ==================== 导航栏 ==================== */
.header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--nav-h);
    background: var(--primary);
    z-index: 1000;
    border-bottom: 2px solid var(--secondary);
    transition: all var(--transition);
    backdrop-filter: blur(0px);
}

/* 滚动后的导航栏 - 始终深色 + 毛玻璃 */
.header.scrolled {
    background: rgba(26, 43, 60, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    box-shadow: 0 2px 20px rgba(0,0,0,0.15);
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 24px;
    max-width: 1200px;
    margin: 0 auto;
    height: var(--nav-h);
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

.logo-img {
    width: 36px;
    height: 36px;
    border-radius: 6px;
}

.logo-text {
    font-size: 18px;
    font-weight: 700;
    color: var(--white);
    letter-spacing: 2px;
}

.nav-list {
    display: flex;
    gap: 4px;
}

.nav-list a {
    font-size: 14px;
    font-weight: 500;
    color: rgba(255,255,255,0.8);
    padding: 8px 14px;
    border-radius: 6px;
    transition: all var(--transition);
    white-space: nowrap;
    position: relative;
}

.nav-list a:hover {
    color: var(--white);
    background: rgba(255,255,255,0.1);
}

.nav-list a::after {
    content: '';
    position: absolute;
    bottom: 2px;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--secondary);
    transition: all var(--transition);
    transform: translateX(-50%);
    border-radius: 1px;
}

.nav-list a:hover::after {
    width: 60%;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 6px;
    z-index: 1001;
}

.nav-toggle span {
    width: 24px; height: 2px;
    background: var(--white);
    border-radius: 2px;
    transition: var(--transition);
}

.nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}
.nav-toggle.active span:nth-child(2) {
    opacity: 0;
}
.nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

/* ==================== 封面 ==================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary) 0%, var(--dark) 100%);
    padding: 80px 24px 60px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.3;
}

.hero-content {
    position: relative;
    text-align: center;
    color: var(--white);
}

.hero h1 {
    font-size: clamp(26px, 4.5vw, 44px);
    font-weight: 700;
    margin-bottom: 16px;
    line-height: 1.3;
    text-shadow: 0 2px 20px rgba(0,0,0,0.3);
}

.hero-subtitle {
    font-size: clamp(16px, 2.5vw, 22px);
    opacity: 0.9;
    margin-bottom: 28px;
}

.hero-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    justify-content: center;
    margin-bottom: 44px;
}

.hero-tags span {
    background: rgba(43,122,191,0.45);
    padding: 8px 22px;
    border-radius: 24px;
    font-size: 14px;
    font-weight: 500;
    border: 1px solid rgba(255,255,255,0.12);
    backdrop-filter: blur(4px);
}

.hero-stats {
    display: flex;
    gap: 60px;
    justify-content: center;
    padding-top: 32px;
    border-top: 1px solid rgba(255,255,255,0.12);
}

.hero-stats .stat {
    text-align: center;
}

.hero-stats .stat strong {
    display: block;
    font-size: 40px;
    font-weight: 700;
    color: var(--secondary);
}

.hero-stats .stat span {
    font-size: 14px;
    opacity: 0.65;
}

/* ==================== 通用区块 ==================== */
.section {
    padding: 80px 0;
    position: relative;
}

.section-bg {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    opacity: 0.06;
    pointer-events: none;
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
    position: relative;
    z-index: 1;
}

.section-header h2 {
    font-size: 32px;
    color: var(--primary);
    margin-bottom: 10px;
    position: relative;
    display: inline-block;
}

.section-header h2::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: var(--secondary);
    margin: 12px auto 0;
    border-radius: 2px;
}

.section-header.light h2 {
    color: var(--white);
}

.section-header.light h2::after {
    background: rgba(255,255,255,0.5);
}

.section-header.light p {
    color: rgba(255,255,255,0.65);
}

.section-header p {
    font-size: 15px;
    color: var(--text-light);
    margin-top: 6px;
}

/* ==================== 关于我们 ==================== */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: start;
}

.about-text p {
    margin-bottom: 18px;
    color: var(--text-light);
    font-size: 15px;
    line-height: 1.8;
}

.about-info {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.info-card {
    background: var(--light);
    padding: 28px 20px;
    border-radius: var(--radius);
    text-align: center;
    border-left: 3px solid var(--secondary);
    transition: transform var(--transition), box-shadow var(--transition);
}

.info-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

/* SVG 图标容器 - 大气 */
.info-icon {
    width: 52px;
    height: 52px;
    margin: 0 auto 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--secondary), #3498db);
    border-radius: 14px;
    box-shadow: 0 4px 12px rgba(43,122,191,0.25);
}

.info-icon svg {
    width: 26px;
    height: 26px;
    fill: var(--white);
}

.info-card h3 {
    font-size: 15px;
    color: var(--primary);
    margin-bottom: 8px;
    font-weight: 600;
}

.info-card p { font-size: 13px; color: var(--text-light); line-height: 1.7; }

/* ==================== 核心优势 ==================== */
.advantages {
    background: var(--light);
}

.adv-grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    gap: 20px;
}

.adv-card {
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform var(--transition), box-shadow var(--transition);
    cursor: default;
}

.adv-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.adv-card img {
    width: 100%;
    height: 160px;
    object-fit: cover;
}

.adv-info {
    padding: 14px 12px;
    background: var(--white);
    text-align: center;
}

.adv-info h4 { font-size: 15px; color: var(--primary); margin-bottom: 4px; font-weight: 600; }
.adv-info p { font-size: 12px; color: var(--text-light); }

/* ==================== 业务版块 ==================== */
.business {
    background: var(--light);
}

.electronic, .pipe {
    background: var(--white);
    overflow: hidden;
}

.business-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.business-content.reverse { direction: rtl; }
.business-content.reverse > * { direction: ltr; }

.business-badge {
    display: inline-block;
    background: var(--secondary);
    color: var(--white);
    padding: 5px 16px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 12px;
    letter-spacing: 1px;
}

.business-info h3 {
    font-size: 24px;
    color: var(--primary);
    margin-bottom: 12px;
    font-weight: 700;
}

.business-info > p {
    color: var(--text-light);
    margin-bottom: 18px;
    font-size: 15px;
}

.business-features { margin-bottom: 20px; }
.business-features li {
    padding: 7px 0;
    color: var(--text);
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.business-features li svg {
    width: 16px;
    height: 16px;
    fill: #27ae60;
    flex-shrink: 0;
}

.business-contact {
    background: var(--light);
    padding: 14px 20px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    gap: 12px;
    border-left: 3px solid var(--accent);
}

.contact-label { color: var(--text-light); font-size: 13px; }
.contact-phone { font-size: 18px; font-weight: 700; color: var(--accent); }

.img-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.img-grid img {
    width: 100%;
    height: 180px;
    object-fit: cover;
    border-radius: var(--radius);
    transition: transform var(--transition);
}

.img-grid img:hover { transform: scale(1.03); }

/* ==================== 环境展示 ==================== */
.env-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.env-card {
    position: relative;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.env-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.env-card:hover img { transform: scale(1.08); }

.env-info {
    position: absolute;
    bottom: 0; left: 0; right: 0;
    background: linear-gradient(transparent, rgba(0,0,0,0.8));
    color: var(--white);
    padding: 40px 16px 16px;
}

.env-info h4 { font-size: 15px; margin-bottom: 4px; font-weight: 600; }
.env-info p { font-size: 12px; opacity: 0.85; }

/* ==================== 产品展示 ==================== */
.products { background: var(--light); }

.tabs {
    display: flex;
    justify-content: center;
    gap: 12px;
    margin-bottom: 30px;
}

.tab-btn {
    padding: 10px 28px;
    border: 2px solid var(--secondary);
    background: transparent;
    color: var(--secondary);
    font-size: 14px;
    font-weight: 600;
    border-radius: 30px;
    cursor: pointer;
    transition: all var(--transition);
}

.tab-btn:hover, .tab-btn.active {
    background: var(--secondary);
    color: var(--white);
    box-shadow: 0 4px 16px rgba(43,122,191,0.3);
}

.tab-content { display: none; }
.tab-content.active { display: block; }

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

.product-card {
    background: var(--white);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform var(--transition), box-shadow var(--transition);
}

.product-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.product-card img {
    width: 100%;
    height: 170px;
    object-fit: cover;
}

.product-info { padding: 16px; }
.product-info h4 { font-size: 15px; color: var(--primary); margin-bottom: 6px; font-weight: 600; }
.product-info p { font-size: 13px; color: var(--text-light); }

/* ==================== 联系方式 ==================== */
.contact {
    background: var(--primary);
    color: var(--white);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    position: relative;
    z-index: 1;
}

.contact-card {
    background: rgba(255,255,255,0.06);
    padding: 32px 20px;
    border-radius: var(--radius);
    text-align: center;
    transition: transform var(--transition), background var(--transition);
    border: 1px solid rgba(255,255,255,0.08);
}

.contact-card:hover {
    transform: translateY(-4px);
    background: rgba(255,255,255,0.1);
}

/* 联系方式 SVG 图标 - 大气 */
.contact-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--secondary), #3498db);
    border-radius: 50%;
    box-shadow: 0 4px 16px rgba(43,122,191,0.35);
}

.contact-icon svg {
    width: 28px;
    height: 28px;
    fill: var(--white);
}

.contact-card h3 {
    font-size: 16px;
    color: var(--white);
    margin-bottom: 10px;
    font-weight: 600;
}

.contact-card p {
    font-size: 13px;
    color: rgba(255,255,255,0.7);
    line-height: 1.8;
}

.contact-card .contact-label {
    display: block;
    font-size: 12px;
    color: rgba(255,255,255,0.55);
    margin-bottom: 4px;
}

.phone-link {
    display: block;
    font-size: 20px;
    font-weight: 700;
    color: var(--secondary);
    margin-top: 8px;
    transition: color var(--transition);
}

.phone-link:hover { color: #5dade2; }

/* ==================== 页脚 ==================== */
.footer {
    background: var(--dark);
    color: var(--white);
    padding: 24px 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.footer-logo img { width: 28px; height: 28px; border-radius: 4px; }
.footer-logo span { font-size: 14px; opacity: 0.9; }
.footer p { font-size: 13px; opacity: 0.5; }

/* ==================== 响应式 ==================== */
@media (max-width: 1024px) {
    .adv-grid { grid-template-columns: repeat(3, 1fr); }
    .env-grid { grid-template-columns: repeat(2, 1fr); }
    .product-grid { grid-template-columns: repeat(2, 1fr); }
    .contact-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    :root { --nav-h: 54px; }

    .nav-toggle { display: flex; }

    .nav-list {
        position: fixed;
        top: var(--nav-h);
        left: 0; right: 0;
        background: rgba(26, 43, 60, 0.97);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        flex-direction: column;
        padding: 0 24px;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.35s ease;
        border-bottom: 2px solid var(--secondary);
    }

    .nav-list.active { max-height: 500px; padding: 10px 24px; }

    .nav-list li a {
        display: block;
        padding: 12px 0;
        border-bottom: 1px solid rgba(255,255,255,0.08);
        color: rgba(255,255,255,0.85);
    }

    .nav-list a::after { display: none; }

    .about-content { grid-template-columns: 1fr; }
    .about-info { grid-template-columns: 1fr 1fr; }
    .business-content { grid-template-columns: 1fr; }
    .business-content.reverse { direction: ltr; }
    .adv-grid { grid-template-columns: repeat(2, 1fr); }
    .section { padding: 60px 0; }
    .section-header h2 { font-size: 24px; }
    .hero { padding: 70px 24px 50px; min-height: auto; }
    .hero-stats { gap: 30px; }
    .hero-stats .stat strong { font-size: 28px; }
}

@media (max-width: 480px) {
    .about-info { grid-template-columns: 1fr; }
    .adv-grid { grid-template-columns: 1fr 1fr; }
    .env-grid { grid-template-columns: 1fr 1fr; }
    .product-grid { grid-template-columns: 1fr 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .tabs { flex-direction: column; align-items: stretch; }
    .tab-btn { text-align: center; }
    .img-grid { grid-template-columns: 1fr 1fr; }
    .img-grid img { height: 140px; }
    .business-contact { flex-direction: column; text-align: center; }
    .hero-stats { flex-direction: column; gap: 16px; }
    .footer-content { flex-direction: column; gap: 10px; text-align: center; }
    .map-wrapper { flex-direction: column; }
    .map-container { height: 300px; }
}

/* ==================== 地图导航 ==================== */
.map-section {
    background: var(--white);
}

.map-wrapper {
    display: flex;
    gap: 24px;
    align-items: stretch;
}

.map-container {
    flex: 1;
    min-height: 420px;
    border-radius: var(--radius);
    overflow: hidden;
    border: 2px solid #e8ecf1;
    box-shadow: var(--shadow);
}

.map-info {
    width: 300px;
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.map-info-card {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 16px;
    background: var(--light);
    border-radius: var(--radius);
    font-size: 14px;
    line-height: 1.6;
    color: var(--text);
}

.map-info-card svg {
    flex-shrink: 0;
    margin-top: 2px;
}

.map-nav-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 24px;
    background: var(--secondary);
    color: var(--white);
    border-radius: var(--radius);
    font-size: 15px;
    font-weight: 600;
    transition: all var(--transition);
    box-shadow: 0 4px 16px rgba(43,122,191,0.3);
}

.map-nav-btn:hover {
    background: #2368a8;
    transform: translateY(-2px);
    box-shadow: 0 6px 24px rgba(43,122,191,0.4);
}

/* 地图标记样式 */
.map-marker { background: none !important; border: none !important; }

/* Leaflet 弹窗样式 */
.leaflet-popup-content-wrapper {
    border-radius: 10px !important;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15) !important;
}
.leaflet-popup-tip { box-shadow: 0 2px 8px rgba(0,0,0,0.1) !important; }

@media (max-width: 768px) {
    .map-wrapper {
        flex-direction: column;
    }
    .map-container {
        min-height: 320px;
    }
    .map-info {
        width: 100%;
    }
}

/* ==================== FAQ 常见问题 ==================== */
.faq {
    background: var(--white);
}

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

.faq-item {
    background: var(--light);
    border-radius: var(--radius);
    margin-bottom: 12px;
    overflow: hidden;
    transition: box-shadow var(--transition);
}

.faq-item:hover {
    box-shadow: var(--shadow);
}

.faq-item summary {
    padding: 18px 24px;
    font-weight: 600;
    font-size: 15px;
    color: var(--primary);
    cursor: pointer;
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    user-select: none;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
    content: '+';
    font-size: 22px;
    font-weight: 300;
    color: var(--secondary);
    transition: transform var(--transition);
}

.faq-item[open] summary::after {
    content: '−';
    transform: rotate(180deg);
}

.faq-answer {
    padding: 0 24px 18px;
    font-size: 14px;
    line-height: 1.8;
    color: var(--text);
}

/* ==================== 信任背书 ==================== */
.trust {
    background: var(--primary);
    padding: 50px 0;
}

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

.trust-item {
    padding: 24px 16px;
}

.trust-num {
    font-size: 32px;
    font-weight: 800;
    color: var(--secondary);
    line-height: 1.2;
    margin-bottom: 6px;
}

.trust-label {
    font-size: 16px;
    font-weight: 600;
    color: var(--white);
    margin-bottom: 6px;
}

.trust-desc {
    font-size: 13px;
    color: rgba(255,255,255,0.55);
}

@media (max-width: 768px) {
    .trust-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }
    .trust-num { font-size: 26px; }
}

@media (max-width: 480px) {
    .trust-grid {
        grid-template-columns: 1fr 1fr;
    }
}