:root {
    --primary-blue: #0D47A1;
    --primary-blue-light: #1976D2;
    --accent-yellow: #FFC107;
    --text-color: #222;
    --text-light: #f5f5f5;
    --bg-light: #f7f9fc;
    --bg-dark: #101522;
    --border-color: #e0e0e0;
    --max-width: 1200px;
    --radius: 8px;
    --shadow-soft: 0 10px 25px rgba(0, 0, 0, 0.08);
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Microsoft YaHei", sans-serif;
    color: var(--text-color);
    background: #ffffff;
}

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

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

ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 16px;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 999;
    background: var(--primary-blue);
    color: #ffffff;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo-area {
    display: flex;
    align-items: center;
}

.logo-area img {
    height: 44px;
    width: auto;
    margin-right: 12px;
}

.logo-text {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 1px;
    color: var(--accent-yellow);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 24px;
    font-size: 20px;
}

.nav-links a {
    position: relative;
    padding: 4px 0;
    color: #ffffff;
    opacity: 0.9;
    transition: opacity 0.2s ease, color 0.2s ease;
}

.nav-links a::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -4px;
    width: 0;
    height: 2px;
    background: var(--accent-yellow);
    transition: width 0.2s ease;
}

.nav-links a:hover {
    opacity: 1;
}

.nav-links a:hover::after {
    width: 100%;
}

.nav-lang-separator {
    margin: 0 6px;
    opacity: 0.6;
}

@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
        align-items: flex-start;
        justify-content: center;
        height: auto;
        padding: 10px 0;
    }

    .nav-links {
        flex-wrap: wrap;
        justify-content: flex-start;
        margin-top: 6px;
        gap: 12px 18px;
        font-size: 13px;
    }
}

.section {
    padding: 60px 0;
}

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

.section.dark {
    background: var(--bg-dark);
    color: var(--text-light);
}

.section-title {
    font-size: 26px;
    font-weight: 600;
    margin-bottom: 24px;
    text-align: center;
}

.section-subtitle {
    max-width: 720px;
    margin: 0 auto 40px;
    text-align: center;
    color: #666;
    font-size: 14px;
}

.section-subtitle.light-on-dark {
    color: #d0d4ff;
}

.hero {
    padding: 80px 0 70px;
    background: radial-gradient(circle at top left, #1E88E5, #0D47A1);
    color: #ffffff;
}

.hero-inner {
    display: grid;
    grid-template-columns: 1.3fr 1fr;
    gap: 40px;
    align-items: center;
}

.hero-title {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 16px;
}

.hero-desc {
    font-size: 15px;
    line-height: 1.8;
    margin-bottom: 24px;
    opacity: 0.95;
}

.hero-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.btn-primary {
    display: inline-block;
    padding: 10px 24px;
    border-radius: 999px;
    background: var(--accent-yellow);
    color: #111;
    font-weight: 600;
    font-size: 14px;
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.25);
    transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 10px 22px rgba(0, 0, 0, 0.3);
    background: #ffca2c;
}

.btn-outline {
    display: inline-block;
    padding: 9px 22px;
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.7);
    color: #ffffff;
    font-size: 14px;
    opacity: 0.9;
    transition: background 0.15s ease, color 0.15s ease, opacity 0.15s ease;
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.12);
    opacity: 1;
}

.hero-image {
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.45);
    background: rgba(0, 0, 0, 0.2);
    min-height: 220px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 24px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
}

@media (max-width: 1024px) {
    .hero-inner {
        grid-template-columns: 1fr;
    }

    .grid-3 {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .grid-4 {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 640px) {
    .hero {
        padding: 60px 0 50px;
    }

    .hero-title {
        font-size: 24px;
    }

    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
}

.card {
    background: #ffffff;
    border-radius: var(--radius);
    box-shadow: var(--shadow-soft);
    padding: 18px 18px 20px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.card-text-only {
    min-height: 120px;
    justify-content: flex-start;
}

.card.dark {
    background: #151a28;
    color: var(--text-light);
}

.card-img {
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 10px;
    background: #000;
}

.card-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 4px;
}

.card-meta {
    font-size: 13px;
    color: #666;
}

.card-meta.light-on-dark {
    color: #aab2ff;
}

.card-desc {
    font-size: 13px;
    color: #555;
    line-height: 1.7;
}

.card-desc.light-on-dark {
    color: #ccd1ff;
}

.table {
    width: 100%;
    border-collapse: collapse;
    font-size: 13px;
}

.table th,
.table td {
    border: 1px solid var(--border-color);
    padding: 8px 10px;
    text-align: left;
}

.table th {
    background: #f0f4ff;
    font-weight: 600;
}

.cases-hero {
    padding: 60px 0 40px;
    background: radial-gradient(circle at center, #1a237e, #050814);
    color: #ffffff;
}

.case-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
}

@media (max-width: 1024px) {
    .case-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 640px) {
    .case-grid {
        grid-template-columns: 1fr;
    }
}

.case-card {
    position: relative;
    border-radius: 14px;
    overflow: hidden;
    background: #050814;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.6);
    color: #ffffff;
    cursor: pointer;
}

a.case-card-link {
    text-decoration: none;
    color: inherit;
    display: block;
}

a.case-card-link:hover {
    color: inherit;
}

.case-card .case-thumb {
    width: 100%;
    height: 190px;
    overflow: hidden;
    background: #000;
}

.case-card .case-thumb img,
.case-card .case-thumb video {
    width: 100%;
    height: 100%;
    display: block;
}

.case-card .case-thumb img {
    object-fit: contain;
    object-position: center;
}

.case-card .case-thumb video {
    object-fit: cover;
}

.case-card-body {
    padding: 12px 14px 14px;
    background: linear-gradient(to bottom, rgba(0, 0, 0, 0.5), #050814);
}

.case-card-title {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 4px;
}

.case-card-meta {
    font-size: 12px;
    color: #b0bec5;
    margin-bottom: 4px;
}

.case-card-desc {
    font-size: 12px;
    line-height: 1.7;
    color: #e0e0e0;
}

.video-section {
    margin-top: 40px;
}

.video-wrapper {
    position: relative;
    padding-top: 56.25%;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.7);
    background: #000;
}

.video-wrapper iframe,
.video-wrapper video {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
}

/* 案例弹层：多图翻页 / 视频放大自动播放 */
.case-lightbox {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0,0,0,0.9);
    align-items: center;
    justify-content: center;
    padding: 20px 70px;
    cursor: zoom-out;
}

.case-lightbox.active {
    display: flex;
}

.case-lightbox-content {
    position: relative;
    max-width: 95vw;
    max-height: 90vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.case-lightbox-content img {
    max-width: 100%;
    max-height: 85vh;
    width: auto;
    height: auto;
    object-fit: contain;
    border-radius: 8px;
    pointer-events: none;
}

.case-lightbox-content video {
    max-width: 95vw;
    max-height: 90vh;
    width: auto;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.5);
}

.case-lightbox-prev,
.case-lightbox-next {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 50px;
    height: 50px;
    border: none;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 28px;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.case-lightbox-prev:hover,
.case-lightbox-next:hover {
    background: rgba(255,255,255,0.35);
}

.case-lightbox-prev { left: 12px; }
.case-lightbox-next { right: 12px; }

.case-lightbox-close {
    position: absolute;
    top: 16px;
    right: 16px;
    width: 46px;
    height: 46px;
    border: none;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 28px;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.case-lightbox-close:hover {
    background: rgba(255,255,255,0.35);
}

.case-lightbox.has-video .case-lightbox-prev,
.case-lightbox.has-video .case-lightbox-next {
    display: none;
}

.about-layout {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 32px;
    align-items: start;
}

@media (max-width: 900px) {
    .about-layout {
        grid-template-columns: 1fr;
    }
}

.contact-block {
    padding: 16px 18px;
    border-radius: var(--radius);
    box-shadow: var(--shadow-soft);
    background: #ffffff;
    font-size: 14px;
    line-height: 1.8;
}

.contact-block h3 {
    margin-top: 0;
    margin-bottom: 8px;
    font-size: 16px;
}

.map-wrapper {
    margin-top: 14px;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 10px 24px rgba(0, 0, 0, 0.2);
}

/* ========== 产品页：四类品类 + 图片自适应 ========== */
.product-tabs {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 8px;
    margin-bottom: 28px;
    border-bottom: 2px solid var(--border-color);
    padding-bottom: 12px;
}

.product-tabs button {
    padding: 10px 20px;
    border: 1px solid var(--border-color);
    background: #e3eaf2;
    color: var(--text-color);
    font-size: 15px;
    font-weight: 500;
    border-radius: var(--radius);
    cursor: pointer;
    transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.product-tabs button:hover {
    background: var(--bg-light);
    border-color: var(--primary-blue-light);
    color: var(--primary-blue);
}

.product-tabs button.active {
    background: var(--primary-blue);
    border-color: var(--primary-blue);
    color: #fff;
}

.product-tab-panel {
    display: none;
}

.product-tab-panel.active {
    display: block;
}

.product-category-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--primary-blue);
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}

.product-item {
    background: #fff;
    border-radius: var(--radius);
    box-shadow: var(--shadow-soft);
    overflow: hidden;
    padding: 14px;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.product-item-title {
    font-size: 15px;
    font-weight: 600;
    margin: 0;
    color: var(--text-color);
}

.product-img-wrap {
    position: relative;
    width: 100%;
    background: #f5f5f5;
    border-radius: 8px;
    overflow: hidden;
    min-height: 120px;
}

.product-img-wrap img {
    width: 100%;
    height: auto;
    max-height: 320px;
    object-fit: contain;
    object-position: center;
    display: block;
    cursor: zoom-in;
    transition: transform 0.2s ease;
}

.product-img-wrap img:hover {
    transform: scale(1.02);
}

.product-img-wrap .product-img-label {
    position: absolute;
    top: 6px;
    left: 8px;
    font-size: 11px;
    color: #666;
    background: rgba(255,255,255,0.9);
    padding: 2px 6px;
    border-radius: 4px;
}

.product-lightbox {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: rgba(0,0,0,0.85);
    align-items: center;
    justify-content: center;
    padding: 20px 60px;
    cursor: zoom-out;
}

.product-lightbox.active {
    display: flex;
}

.product-lightbox img {
    max-width: calc(95vw - 120px);
    max-height: 90vh;
    width: auto;
    height: auto;
    object-fit: contain;
    cursor: default;
    border-radius: 8px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.5);
    pointer-events: none;
}

.lightbox-prev,
.lightbox-next {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    width: 48px;
    height: 48px;
    border: none;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 32px;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
    flex-shrink: 0;
}

.lightbox-prev:hover,
.lightbox-next:hover {
    background: rgba(255,255,255,0.35);
}

.lightbox-prev {
    left: 12px;
}

.lightbox-next {
    right: 12px;
}

.lightbox-close {
    position: absolute;
    top: 16px;
    right: 16px;
    width: 44px;
    height: 44px;
    border: none;
    border-radius: 50%;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 28px;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.lightbox-close:hover {
    background: rgba(255,255,255,0.35);
}

@media (max-width: 640px) {
    .product-tabs {
        gap: 6px;
    }

    .product-tabs button {
        padding: 8px 14px;
        font-size: 14px;
    }

    .product-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .product-img-wrap img {
        max-height: 260px;
    }
}

.site-footer {
    padding: 18px 0 24px;
    background: #050714;
    color: #9295b5;
    font-size: 13px;
}

.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

@media (max-width: 640px) {
    .footer-inner {
        flex-direction: column;
        align-items: flex-start;
    }
}