/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    /* 提升默认字体亮度，适配暗色背景 */
    color: #e6e6e6;
    background-color: #000;
    overflow-x: hidden;
    /* ensure content isn't hidden under fixed header */
    padding-top: 80px;
}

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

/* Header */
.header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    z-index: 1000;
    padding: 12px 0;
}

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

.footer {
    padding: 12px 12px;
}

/* Ensure the logo wrapper and image are vertically centered in the header */
.logo {
    display: flex;
    align-items: center;
}

.logo-img {
    display: block; /* remove inline baseline gaps */
    height: 44px;
    width: auto;
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav a:hover {
    color: #ff6b6b;
}

/* Hero Section - make the video a full-bleed background with a subtle overlay */
.hero {
    height: calc(100vh - 80px);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    overflow: hidden;
    background: #000;
}

/* dark gradient overlay over the background video */
.hero::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.45) 0%, rgba(0, 0, 0, 0.65) 100%);
    z-index: 1;
}

.hero-video {
    position: absolute;
    inset: 0;
    z-index: 0;
    display: block;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.hero-video video {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.hero-content {
    z-index: 2;
    color: #fff;
    max-width: 100%;
    padding: 40px 20px;
}

.hero h1 {
    font-size: 3.6rem;
    font-weight: 800;
    margin-bottom: 0.6rem;
    line-height: 1.02;
    letter-spacing: -1px;
    color: #ffffff;
    text-shadow: 0 6px 30px rgba(0, 0, 0, 0.7);
}

.hero-subtitle {
    font-size: 2rem;
    margin-bottom: 1.6rem;
    opacity: 1; /* 更清晰 */
}

/* Replace boxed hero-video card with background — remove previous boxed shadow */
/* CTA buttons tighter and more pronounced */
.cta-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-top: 1.4rem;
}

.btn-primary, .btn-secondary {
    padding: 12px 28px;
    border: none;
    border-radius: 999px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.22s ease;
}

.btn-primary {
    background: linear-gradient(90deg, #ff6b6b 0%, #4ecdc4 100%);
    color: #fff;
    box-shadow: 0 10px 30px rgba(78, 205, 196, 0.08), 0 6px 18px rgba(255, 107, 107, 0.06);
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.01);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.06);
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.12);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.12);
}

/* Features Section: switch to flex rows so reverse works by flipping direction */
.features {
    padding: 100px 0;
    background: #000;
}

.features h2 {
    text-align: center;
    font-size: 3rem;
    color: #fff;
    margin-bottom: 80px;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.feature-item {
    display: flex;
    gap: 48px;
    align-items: center;
    margin-bottom: 80px;
    flex-wrap: wrap;
}

.feature-item.reverse {
    flex-direction: row-reverse;
}

.feature-content {
    color: #fff;
    flex: 1 1 420px;
}

.feature-media {
    flex: 1 1 420px;
}

.feature-content h3 {
    font-size: 2.2rem;
    margin-bottom: 1rem;
    color: #4ecdc4;
}

.feature-content p {
    font-size: 1.1rem;
    line-height: 1.8;
    /* 显示更明亮 */
    opacity: 1;
    margin-bottom: 1.4rem;
}

.feature-icon {
    width: 72px;
    height: 72px;
    object-fit: contain;
    margin-top: 12px;
}

.feature-media video {
    width: 100%;
    height: 320px;
    border-radius: 14px;
    object-fit: cover;
    box-shadow: 0 18px 40px rgba(0, 0, 0, 0.6);
}

/* Gallery Section */
.gallery {
    padding: 80px 0;
    background: #0b0b0b;
}

.gallery h2 {
    text-align: center;
    font-size: 2.8rem;
    color: #fff;
    margin-bottom: 40px;
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
}

.gallery-item {
    border-radius: 14px;
    overflow: hidden;
    position: relative;
    transition: transform 0.28s ease, box-shadow 0.28s ease;
}

.gallery-item:hover {
    transform: translateY(-6px) scale(1.02);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.6);
}

.gallery-item img {
    width: 100%;
    height: 260px;
    object-fit: cover;
    display: block;
}

/* simple subtle overlay caption on hover (keeps layout clean) */
.gallery-item::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0) 40%, rgba(0, 0, 0, 0.45) 100%);
    opacity: 0;
    transition: opacity 0.28s ease;
}

.gallery-item:hover::after {
    opacity: 1;
}

/* Specifications Section */
.specifications {
    padding: 100px 0;
    background: #000;
    text-align: center;
}

.specifications h2 {
    font-size: 2.8rem;
    color: #fff;
    margin-bottom: 40px;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.specs-image {
    max-width: 100%;
    height: auto;
    border-radius: 14px;
}

/* Coming Soon Section */
.coming-soon {
    padding: 80px 0;
    background: #0b0b0b;
    text-align: center;
}

.coming-soon-image {
    max-width: 100%;
    height: auto;
}

/* Contact Section */
.contact {
    padding: 80px 0;
    background: #000;
    text-align: center;
}

.contact h2 {
    font-size: 2.4rem;
    color: #fff;
    margin-bottom: 40px;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.contact-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 30px;
}

.connect-image {
    max-width: 320px;
    height: auto;
}

.contact-info {
    color: #efefef; /* 稍微亮一点 */
}

.contact-info p {
    font-size: 1.1rem;
    margin-bottom: 10px;
}

/* Intro (above banner) */
.intro-section {
    padding: 40px 0;
    background: #000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.intro-inner {
    max-width: 1200px;
    width: 100%;
    padding: 0 20px;
    box-sizing: border-box;
    text-align: left;
}

.intro-title {
    color: #fff;
    font-size: clamp(28px, 4.5vw, 56px);
    margin: 0 0 8px;
    font-weight: 800;
    text-align: left;
}

.divider {
    display: block;
    width: clamp(80px, 12vw, 220px);
    height: auto;
    margin: 6px 0 14px 0;
}

.intro-copy {
    color: rgba(255, 255, 255, 0.94);
    font-size: clamp(16px, 2vw, 20px);
    line-height: 1.6;
    margin: 0;
}

/* Full-screen banner area */
.banner-section {
    height: 100vh;
    width: 100%;
    background: #000;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.banner-overlay {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    pointer-events: none;
}

.banner-inner {
    max-width: 1200px;
    width: 100%;
    padding: 0 20px;
    box-sizing: border-box;
    text-align: center;
}

.banner-title-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    animation: fadeInUp 0.8s ease-out 0.12s both;
}

.banner-title {
    color: #fff;
    font-size: clamp(28px, 4.5vw, 56px);
    margin: 0;
    font-weight: 800;
    text-shadow: 0 8px 30px rgba(0, 0, 0, 0.6);
}

.banner-divider {
    display: block;
    width: clamp(80px, 12vw, 220px);
    height: auto;
}

.banner-copy {
    color: rgba(255, 255, 255, 0.95);
    font-size: clamp(14px, 1.8vw, 20px);
    line-height: 1.6;
    margin: 0;
    text-shadow: 0 6px 20px rgba(0, 0, 0, 0.45);
    text-align: center;
}

/* Banner carousel */
.banner-carousel {
    padding: 0;
    background: transparent;
    width: 100vw;
    position: relative;
    left: 50%;
    right: 50%;
    margin-left: -50vw;
    margin-right: -50vw;
}

.carousel {
    width: 100%;
    margin: 0;
    position: relative;
    display: flex;
    align-items: center;
}

.carousel-track-wrapper {
    overflow: hidden;
    width: 100%;
}

.carousel-track {
    display: flex;
    align-items: center;
    gap: 16px;
    list-style: none;
    padding: 12px;
    margin: 0;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
    overflow-x: auto;
    scroll-behavior: smooth;
}

.carousel-item {
    scroll-snap-align: center;
    flex: 0 0 auto;
    display: flex;
    align-items: center;
    justify-content: center;
}

.carousel-item img {
    height: 300px;
    width: auto;
    max-width: none;
    object-fit: cover;
    display: block;
    border-radius: 8px;
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.45);
}

.carousel-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 0, 0, 0.5);
    border: none;
    color: #fff;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 5;
}

.carousel-btn:focus {
    outline: 2px solid #4ecdc4;
    outline-offset: 3px;
}

.carousel-btn.prev {
    left: 8px;
}

.carousel-btn.next {
    right: 8px;
}

/* Pagination dots */
.carousel-dots {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin-top: 14px;
}

.carousel-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.18);
    border: none;
    cursor: pointer;
}

.carousel-dot[aria-pressed="true"], .carousel-dot.active {
    background: #4ecdc4;
}

.carousel-dot:focus {
    outline: 2px solid #4ecdc4;
    outline-offset: 3px;
}

/* Screen-reader only utility */
.sr-only {
    position: absolute !important;
    height: 1px;
    width: 1px;
    overflow: hidden;
    clip: rect(1px, 1px, 1px, 1px);
    white-space: nowrap;
    border: 0;
    padding: 0;
    margin: -1px;
}

/* Responsive: adjust carousel image heights on smaller screens (keep full-width items) */
@media (max-width: 900px) {
    .carousel-item img {
        height: 260px;
    }
}

@media (max-width: 600px) {
    .carousel-item img {
        height: 220px;
    }

    .carousel-btn.prev {
        left: 6px;
    }

    .carousel-btn.next {
        right: 6px;
    }
}

/* Hide native scrollbars for the carousel track */
.carousel-track {
    -ms-overflow-style: none;
    scrollbar-width: none;
}

.carousel-track::-webkit-scrollbar {
    display: none;
    width: 0;
    height: 0;
}

/* Carousel header: title left + copy right, divider under title left-aligned */
.carousel-header {
    margin: 24px auto 12px;
    padding: 0 20px;
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 24px;
}

.carousel-header > div {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.carousel-title {
    color: #fff;
    font-size: clamp(26px, 3.6vw, 40px);
    font-weight: 800;
    margin: 0;
    line-height: 1.02;
}

.carousel-copy {
    color: rgba(255, 255, 255, 0.88);
    font-size: clamp(14px, 1.4vw, 18px);
    max-width: 55%;
    margin: 6px 0 0 0;
}

.carousel-divider-left {
    display: block;
    width: clamp(80px, 12vw, 220px);
    height: auto;
    margin-top: 10px;
}

@media (max-width: 800px) {
    .carousel-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .carousel-copy {
        max-width: 100%;
        margin-top: 12px;
    }
}

/* Three-image horizontal row used for open/connect/about_bg */
.three-row {
    display: flex;
    gap: 20px;
    justify-content: center;
    align-items: stretch;
    padding: 48px 0;
    background: #000;
    box-sizing: border-box;
}

.three-row .three-inner {
    max-width: 1200px;
    width: 100%;
    padding: 0 20px;
    margin: 0 auto;
    display: flex;
    gap: 20px;
    justify-content: space-between;
    align-items: center;
    box-sizing: border-box;
}

.three-row .three-item {
    flex: 1 1 calc(33.333% - 20px);
    display: flex;
    align-items: center;
    justify-content: center;
}

.three-row .three-item img {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 12px;
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.45);
    transition: transform 0.36s ease, box-shadow 0.36s ease;
    object-fit: cover;
}

.three-row .three-item:hover img {
    transform: translateY(-6px) scale(1.02);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.6);
}

/* Three-image captions */
.three-caption {
    margin-top: 12px;
    color: rgba(255, 255, 255, 0.92);
    font-size: 1.5rem;
    font-weight: 600;
    text-align: center;
}

@media (max-width: 980px) {
    .three-row .three-item {
        flex: 1 1 48%;
    }
}

@media (max-width: 640px) {
    .three-row {
        padding: 28px 0;
    }

    .three-row .three-inner {
        flex-direction: column;
        gap: 18px;
    }

    .three-row .three-item {
        width: 100%;
        flex: 0 0 auto;
    }
}

/* Contact row for footer-like contact area */
.contact-section {
    background: #000;
    padding: 28px 20px;
    box-sizing: border-box;
}

.contact-row {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.contact-left {
    display: flex;
    align-items: center;
    gap: 16px;
}

.contact-left img.logo-small {
    height: 44px;
    width: auto;
    display: block;
}

.contact-email-left {
    color: #fff;
    font-size: 1.2rem; /* slightly larger */
    font-weight: 700;
    text-decoration: none;
}

.contact-right {
    color: #fff;
    text-align: right;
    font-size: 1.2rem; /* slightly larger */
}

@media (max-width: 800px) {
    .contact-row {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .contact-right {
        text-align: center;
    }

    .contact-left {
        justify-content: center;
    }

    .contact-left img.logo-small {
        height: 40px;
    }
}

/* Responsive Design */
@media (max-width: 1024px) {
    .hero h1 {
        font-size: 2.8rem;
    }

    .feature-media video {
        height: 260px;
    }
}

@media (max-width: 768px) {
    .hero {
        height: auto;
        padding: 60px 0;
    }

    .hero h1 {
        font-size: 2.2rem;
    }

    .hero-subtitle {
        font-size: 1.05rem;
    }

    .feature-item {
        flex-direction: column;
        text-align: center;
    }

    .feature-item.reverse {
        flex-direction: column; /* don't reverse on small screens */
    }

    .cta-buttons {
        flex-direction: column;
        align-items: center;
    }

    .nav ul {
        flex-direction: column;
        gap: 15px;
    }

    .header .container {
        flex-direction: row;
        gap: 12px;
    }

    .features h2,
    .gallery h2,
    .specifications h2,
    .contact h2 {
        font-size: 1.8rem;
    }

    .feature-content h3 {
        font-size: 1.6rem;
    }
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}

/* Loading Animation */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(18px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feature-item,
.gallery-item {
    animation: fadeInUp 0.6s ease-out;
}

.lazy-img {
    display: block;
    width: 100%;
    height: auto;
    max-width: 100%;
}