/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent !important;
}

html {
    scroll-behavior: smooth;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: rgba(0, 0, 0, 0.2);
}

::-webkit-scrollbar-thumb {
    background: rgba(77, 166, 255, 0.5);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(77, 166, 255, 0.8);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Arial', sans-serif;
    line-height: 1.7;
    color: #ffffff;
    background: #000;
    overflow-x: hidden;
    font-weight: 400;
    letter-spacing: 0.3px;
    font-size: 16px;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-weight: 700;
    letter-spacing: -0.8px;
    line-height: 1.2;
    margin-bottom: 1.5rem;
    background: linear-gradient(135deg, #ffffff 0%, #e0e6ff 50%, #c7d2fe 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
    font-optical-sizing: auto;
}

p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
    line-height: 1.8;
    font-weight: 400;
    color: rgba(255, 255, 255, 0.9);
    letter-spacing: 0.3px;
}

a {
    text-decoration: none;
    color: #4da6ff;
    transition: all 0.3s ease;
    position: relative;
}

a:hover {
    color: #80c2ff;
}

a:not(.nav-link):not(.cta-button):after {
    content: '';
    position: absolute;
    width: 0;
    height: 1px;
    bottom: -2px;
    left: 0;
    background-color: #80c2ff;
    transition: width 0.3s ease;
}

a:not(.nav-link):not(.cta-button):hover:after {
    width: 100%;
}

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

/* Starfield Background */
#starfield {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    background-color: #000;
}

/* Particles Canvas */
#particles-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(0, 0, 0, 0.7); /* 更透明 */
    backdrop-filter: blur(15px); /* 增加模糊效果 */
    -webkit-backdrop-filter: blur(15px);
    z-index: 1000;
    transition: all 0.3s ease;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1); /* 添加微妙的边框 */
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3); /* 添加阴影 */
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700; /* 更粗的字体 */
    color: #ffffff;
    text-decoration: none;
    letter-spacing: -0.5px; /* 紧凑的字母间距 */
}

.logo-icon {
    font-size: 2rem;
    background: linear-gradient(135deg, #4da6ff, #a0a0ff); /* 更改渐变颜色 */
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 15px rgba(77, 166, 255, 0.5); /* 添加发光效果 */
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: #ffffff;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
    padding: 8px 16px;
    border-radius: 8px;
    position: relative;
    letter-spacing: 0.5px; /* 增加字母间距 */
}

.nav-link:hover,
.nav-link.active {
    color: #4da6ff; /* 更改悬停颜色 */
    background: rgba(77, 166, 255, 0.1); /* 添加微妙的背景 */
    box-shadow: 0 0 10px rgba(77, 166, 255, 0.2); /* 添加发光效果 */
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: #ffffff;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    position: relative;
    z-index: 1;
}

.hero-container {
    max-width: 800px;
    padding: 0 20px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    animation: fadeInUp 1s ease-out both;
    background: linear-gradient(135deg, #ffffff, #a0a0ff); /* 标题渐变效果 */
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 30px rgba(160, 160, 255, 0.5); /* 增强发光效果 */
    letter-spacing: -1px; /* 紧凑的字母间距 */
    line-height: 1.2; /* 更紧凑的行高 */
}

.title-main {
    display: block;
    background: linear-gradient(135deg, #ffffff, #a0a0ff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
    text-shadow: 0 0 30px rgba(160, 160, 255, 0.5);
    font-size: 1em;
}

.title-english {
    display: block;
    font-size: 0.6em;
    color: #a0a0ff;
    font-weight: 400;
    letter-spacing: 2px;
    text-transform: uppercase;
    opacity: 0.9;
}

.hero-description {
    font-size: 1.2rem;
    color: #e0e0e0;
    margin-bottom: 2.5rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 1s ease-out 0.3s both;
}

.cta-button {
    display: inline-block;
    background: linear-gradient(135deg, #4da6ff, #6a8fff); /* 更改为蓝色系渐变 */
    color: #ffffff;
    padding: 15px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    box-shadow: 0 10px 30px rgba(77, 166, 255, 0.3); /* 匹配蓝色阴影 */
    animation: fadeInUp 1s ease-out 0.6s both;
    border: 1px solid rgba(255, 255, 255, 0.1); /* 添加微妙的边框 */
    letter-spacing: 0.5px; /* 增加字母间距 */
    position: relative;
    overflow: hidden;
}

.cta-button:before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: all 0.6s ease;
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(77, 166, 255, 0.4); /* 匹配蓝色阴影 */
    background: linear-gradient(135deg, #3a93ff, #5a7fff); /* 更深的蓝色渐变 */
}

.cta-button:hover:before {
    left: 100%;
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: bounce 2s infinite;
}

.scroll-arrow {
    width: 20px;
    height: 20px;
    border-right: 2px solid #ffffff;
    border-bottom: 2px solid #ffffff;
    transform: rotate(45deg);
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(-50%) translateY(0);
    }
    40% {
        transform: translateX(-50%) translateY(-10px);
    }
    60% {
        transform: translateX(-50%) translateY(-5px);
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* User Videos Section */
.user-videos-section {
    min-height: 100vh;
    padding: 80px 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.3), rgba(10, 10, 20, 0.4));
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    max-width: 1200px;
    width: 100%;
    padding: 0 20px;
    margin-bottom: 40px;
}

.video-item {
    position: relative;
    border-radius: 20px;
    overflow: hidden;
    background: transparent;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s ease;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    aspect-ratio: 16/9;
}

.video-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.4);
    border-color: rgba(255, 107, 107, 0.3);
}

/* 仅添加装饰性播放图标（右下角），不改变交互行为 */
.user-videos-section .video-item::after {
  content: '▶';
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 56px;
  height: 56px;
  font-size: 1.6rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  background: rgba(255, 107, 107, 0.9);
  border-radius: 50%;
  box-shadow: 0 8px 20px rgba(255, 107, 107, 0.35);
  pointer-events: none;
  z-index: 1;
}

/* 原尺寸视频模态播放器 */
.video-modal {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  background: rgba(0,0,0,0.35);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 2000;
}
.video-modal .modal-inner {
  position: relative;
  max-width: 90vw;
  max-height: 90vh;
}
.video-modal video {
  width: auto; height: auto;
  max-width: 90vw; max-height: 90vh;
  border-radius: 12px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.6);
}
.video-modal .video-close {
  position: absolute; top: -12px; right: -12px;
  background: rgba(255,255,255,0.15);
  color: #fff; border: none; border-radius: 50%;
  width: 36px; height: 36px; font-size: 20px;
  cursor: pointer;
}

/* 播放态：自动放大并提升阴影与层级 */
.video-item.video-playing {
    transform: scale(1.06);
    box-shadow: 0 25px 60px rgba(0, 0, 0, 0.5);
    border-color: rgba(255, 107, 107, 0.5);
    z-index: 2;
}
.video-item.video-playing .video-overlay {
    opacity: 0;
    pointer-events: none;
}

.video-item video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

/* Preserve original video size in fullscreen for specific videos */
#new-video-1:fullscreen,
#new-video-2:fullscreen,
#new-video-1:-webkit-full-screen,
#new-video-2:-webkit-full-screen {
    object-fit: contain;
    width: auto;
    height: auto;
}

/* Modal video fullscreen displays in original sizing */
#modal-video:fullscreen,
#modal-video:-webkit-full-screen {
    object-fit: contain;
    width: auto;
    height: auto;
}


.video-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: transparent; /* 移除黑色遮罩 */
    display: none; /* 默认不显示遮罩层 */
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: all 0.3s ease;
    pointer-events: none;
}

.video-item:hover .video-overlay { opacity: 0; }

.video-item video:not([controls]) + .video-overlay {
    pointer-events: all;
}

.play-button {
    background: rgba(255, 107, 107, 0.9);
    border: none;
    border-radius: 50%;
    width: 80px;
    height: 80px;
    font-size: 2rem;
    color: white;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 10px 30px rgba(255, 107, 107, 0.3);
}

.play-button:hover {
    background: rgba(255, 107, 107, 1);
    transform: scale(1.1);
    box-shadow: 0 15px 40px rgba(255, 107, 107, 0.5);
}

.videos-content {
    text-align: center;
    max-width: 800px;
    padding: 0 20px;
}

.videos-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #ffffff, #e0e0e0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 30px rgba(255, 255, 255, 0.3);
}

.videos-description {
    font-size: 1.2rem;
    color: #e0e0e0;
    line-height: 1.6;
}

/* Features Section */
.features {
    padding: 100px 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.2), rgba(10, 10, 20, 0.3));
    position: relative;
    z-index: 1;
}

.feature-card {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    padding: 40px;
    margin-bottom: 30px;
    transition: all 0.3s ease;
    transform: translateY(50px);
    opacity: 0;
}

.feature-card.visible {
    transform: translateY(0);
    opacity: 1;
}

.feature-card:hover {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.08);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.feature-title {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #ffffff, #cccccc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.feature-description {
    font-size: 1.1rem;
    color: #e0e0e0;
    line-height: 1.8;
}

/* Particles Section */
.particles-section {
    height: 80vh;
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.particles-video-container {
    position: relative;
    width: 100%;
    height: 100%;
}

.particles-video-container video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0.7;
}

.particles-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    z-index: 2;
}

.particles-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #4ecdc4, #44a08d);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.particles-description {
    font-size: 1.2rem;
    color: #e0e0e0;
}

/* Contact Section */
.contact {
    padding: 80px 0;
    background: linear-gradient(180deg, rgba(10, 10, 20, 0.3), rgba(0, 0, 0, 0.4));
    text-align: center;
    position: relative;
    z-index: 1;
}

.contact-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #ff6b6b, #4ecdc4);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.contact-description {
    font-size: 1.2rem;
    color: #e0e0e0;
    margin-bottom: 2rem;
}

.contact-email {
    display: inline-block;
    color: #4ecdc4;
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    padding: 8px 30px;
    border: 2px solid #4ecdc4;
    border-radius: 50px;
    transition: all 0.3s ease;
}

.contact-email:hover {
    background: #4ecdc4;
    color: #000;
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(78, 205, 196, 0.3);
}

/* Footer */
.footer {
    background: rgba(0, 0, 0, 0.5);
    padding: 40px 0;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    z-index: 1;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: nowrap;
    gap: 20px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.2rem;
    font-weight: 600;
}

.footer-text {
    color: #888;
    font-size: 0.9rem;
}

/* Footer inline layout helpers */
.footer-left {
    flex: 1;
    white-space: normal;
    overflow-wrap: break-word;
    word-break: normal;
    text-align: left;
    line-height: 1.4;
}
.footer-right {
    white-space: nowrap;
    margin-left: 20px;
}

/* Responsive Design */
@media screen and (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: rgba(0, 0, 0, 0.95);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        padding: 20px 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-menu li {
        margin: 10px 0;
    }

    .hamburger {
        display: flex;
    }

    .hamburger.active .bar:nth-child(2) {
        opacity: 0;
    }

    .hamburger.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .hamburger.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-description {
        font-size: 1rem;
    }

    .video-grid {
        grid-template-columns: 1fr;
        gap: 20px;
        padding: 0 15px;
    }

    .video-item {
        min-height: 200px;
    }

    .videos-title {
        font-size: 2rem;
    }

    .videos-description {
        font-size: 1rem;
    }

    .play-button {
        width: 60px;
        height: 60px;
        font-size: 1.5rem;
    }

    .particles-title {
        font-size: 2rem;
    }

    .feature-card {
        padding: 30px 20px;
    }

    .feature-title {
        font-size: 1.5rem;
    }

    .contact-title {
        font-size: 2rem;
    }

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

@media screen and (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .nav-container {
        padding: 0 15px;
    }

    .hero-container {
        padding: 0 15px;
    }

    .feature-card {
        padding: 25px 15px;
    }
}


/* Overview Section */
.overview-section {
    padding: 100px 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.2), rgba(10, 10, 20, 0.3));
    position: relative;
    z-index: 1;
}

.overview-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 2rem;
    background: linear-gradient(135deg, #ffffff 0%, #e0e6ff 50%, #c7d2fe 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
}

.overview-description {
    font-size: 1.2rem;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 0;
}

/* Innovations Section */
.innovations-section {
    padding: 100px 0;
    background: linear-gradient(180deg, rgba(10, 10, 20, 0.3), rgba(0, 0, 0, 0.2));
    position: relative;
    z-index: 1;
}

.innovations-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.innovation-card {
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    padding: 0;
    text-align: center;
    transition: all 0.3s ease;
    transform: translateY(20px);
    opacity: 0;
    animation: fadeInUp 0.6s ease forwards;
    height: 300px;
    position: relative;
    overflow: hidden;
}

.innovation-overlay {
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.3), rgba(0, 0, 0, 0.8));
    backdrop-filter: blur(5px);
    padding: 40px 30px;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    transition: all 0.3s ease;
}

.innovation-card:nth-child(1) { animation-delay: 0.1s; }
.innovation-card:nth-child(2) { animation-delay: 0.2s; }
.innovation-card:nth-child(3) { animation-delay: 0.3s; }
.innovation-card:nth-child(4) { animation-delay: 0.4s; }

.innovation-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    border-color: rgba(77, 166, 255, 0.5);
}

.innovation-card:hover .innovation-overlay {
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.9));
}

.innovation-title {
    font-size: 1.4rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #ffffff;
}

.innovation-description {
    font-size: 1rem;
    line-height: 1.6;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 0;
}

/* Deployment Section */
.deployment-section {
    padding: 100px 0;
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.2), rgba(10, 10, 20, 0.3));
    position: relative;
    z-index: 1;
}

.deployment-content {
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
}

.deployment-stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    margin: 50px 0;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: 700;
    background: linear-gradient(135deg, #4da6ff, #a0a0ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 10px;
    text-shadow: 0 0 20px rgba(77, 166, 255, 0.5);
}

.stat-label {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.8);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.deployment-description {
    font-size: 1.1rem;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 0;
}

/* Applications Section */
.applications-section {
    padding: 100px 0;
    background: linear-gradient(180deg, rgba(10, 10, 20, 0.3), rgba(0, 0, 0, 0.2));
    position: relative;
    z-index: 1;
}

.applications-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 50px;
}

.application-card {
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    padding: 0;
    text-align: center;
    transition: all 0.3s ease;
    transform: translateY(20px);
    opacity: 0;
    animation: fadeInUp 0.6s ease forwards;
    height: 280px;
    position: relative;
    overflow: hidden;
}

.application-overlay {
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.3), rgba(0, 0, 0, 0.8));
    backdrop-filter: blur(5px);
    padding: 30px 25px;
    /* Cover card exactly to keep blur area equal to image */
    position: absolute;
    left: 0; right: 0; top: 0; bottom: 0;
    border-radius: inherit;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    transition: all 0.3s ease;
}

.application-card:nth-child(1) { animation-delay: 0.1s; }
.application-card:nth-child(2) { animation-delay: 0.2s; }
.application-card:nth-child(3) { animation-delay: 0.3s; }
.application-card:nth-child(4) { animation-delay: 0.4s; }

.application-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
    border-color: rgba(77, 166, 255, 0.5);
}

.application-card:hover .application-overlay {
    background: linear-gradient(180deg, rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.9));
}

.application-title {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: #ffffff;
}

.application-description {
    font-size: 0.95rem;
    line-height: 1.6;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 0;
}

/* Enhanced Contact Section */
.contact-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, #4da6ff, #a0a0ff);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    text-shadow: 0 0 20px rgba(77, 166, 255, 0.5);
}

.contact-description {
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 2rem;
    line-height: 1.6;
}

/* Responsive Design for New Sections */
@media screen and (max-width: 768px) {
    .section-title {
        font-size: 1.8rem;
    }
    
    .innovations-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .applications-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .deployment-stats {
        gap: 40px;
    }
    
    .stat-number {
        font-size: 2.5rem;
    }
    
    .innovation-card,
    .application-card {
        padding: 0; /* remove inner padding so overlay aligns */
    }

    /* Ensure mobile card uses consistent aspect ratio with blur overlay */
    .application-card {
        height: auto;
        aspect-ratio: 16/9;
        min-height: 220px;
    }
    .application-overlay {
        padding: 24px 20px;
        backdrop-filter: blur(8px);
    }
    
    .overview-description,
    .deployment-description {
        font-size: 1rem;
    }
}

@media screen and (max-width: 480px) {
    .deployment-stats {
        flex-direction: column;
        gap: 30px;
    }
    
    .innovation-icon,
    .application-icon {
        font-size: 2rem;
    }
    
    .innovation-title,
    .application-title {
        font-size: 1.2rem;
    }
}



/* Modal Styles */
.modal {
    display: none; /* Hidden by default */
    position: fixed; /* Stay in place */
    z-index: 1000; /* Sit on top */
    left: 0;
    top: 0;
    width: 100%; /* Full width */
    height: 100%; /* Full height */
    overflow: auto; /* Enable scroll if needed */
    background-color: rgba(0,0,0,0.4); /* Black w/ opacity */
    justify-content: center;
    align-items: center;
}

.modal-content {
    background-color: #fefefe;
    margin: auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 500px;
    border-radius: 10px;
    position: relative;
    color: #333;
}

.close-button {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
}

.close-button:hover,
.close-button:focus {
    color: black;
    text-decoration: none;
    cursor: pointer;
}

.modal-content h2 {
    text-align: center;
    margin-bottom: 20px;
    color: #333;
}

.modal-content form label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.modal-content form input[type="text"],
.modal-content form input[type="email"],
.modal-content form input[type="tel"],
.modal-content form textarea {
    width: calc(100% - 22px);
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 16px;
}

.modal-content form textarea {
    resize: vertical;
}

.modal-content form button[type="submit"] {
    background-color: #007bff;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    width: 100%;
}

.modal-content form button[type="submit"]:hover {
    background-color: #0056b3;
}

.contact-button {
    background-color: #007bff;
    color: white;
    padding: 12px 25px;
    border: none;
    border-radius: 5px;
    font-size: 1.1em;
    cursor: pointer;
    transition: background-color 0.3s ease;
    text-decoration: none;
    display: inline-block;
    margin-top: 20px;
}

.contact-button:hover {
    background-color: #0056b3;
}



/* Images Section Styles */
.images-section {
    padding: 0;
    background: transparent;
}

.images-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-top: 2rem;
    max-width: 1200px;
    margin-left: auto;
    margin-right: auto;
}

.image-item {
    position: relative;
    background: none;
    border-radius: 0;
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    aspect-ratio: 16/9;
    background-position: center;
    background-size: cover;
    background-repeat: no-repeat;
}

.image-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.4);
}

.achievement-image {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.image-content {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(transparent, rgba(0, 0, 0, 0.8));
    padding: 2rem 1.5rem 1.5rem;
    color: white;
}

.image-title {
    font-size: 1.3rem;
    font-weight: bold;
    color: #ffffff;
    margin-bottom: 0.5rem;
    line-height: 1.3;
}

.image-description {
    font-size: 1rem;
    color: #cccccc;
    line-height: 1.4;
    margin: 0;
}

/* === Fix: remove the blue focus ring around photos/cards (Images Section) === */ 
.images-section .image-item:focus, 
.images-section .image-item:focus-within, 
.images-section .image-item *:focus, 
.images-section .image-item *:focus-visible { 
  outline: none !important; 
  box-shadow: none !important; 
  border-color: transparent !important; 
} 

/* 图片与链接本身不要边框/轮廓 */ 
.images-section .image-item img, 
.images-section .image-item a { 
  border: none !important; 
  outline: none !important; 
} 

/* iOS/Safari 点击高亮与系统焦点色 */ 
:focus { -webkit-focus-ring-color: transparent !important; } 
.images-section .image-item *, 
.images-section .image-item a, 
.images-section .image-item img { 
  -webkit-tap-highlight-color: transparent; 
} 

/* 若主题用 :focus-within 做了阴影/边框，这里统一清空 */ 
.images-section .image-item:focus-within, 
.images-section .image-item:active { 
  box-shadow: none !important; 
  outline: none !important; 
  border: none !important; 
} 

/* —— 若你的视频卡片也出现蓝框，下面一并处理 —— */ 
.user-videos-section .video-item:focus, 
.user-videos-section .video-item:focus-within, 
.user-videos-section .video-item *:focus, 
.user-videos-section .video-item *:focus-visible { 
  outline: none !important; 
  box-shadow: none !important; 
  border-color: transparent !important; 
} 
.user-videos-section .video-item video, 
.user-videos-section .video-item a { 
  border: none !important; 
  outline: none !important; 
} 
.user-videos-section .video-item *, 
.user-videos-section .video-item a, 
.user-videos-section .video-item video { 
  -webkit-tap-highlight-color: transparent; 
}

@media (max-width: 768px) {
    .images-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .image-title {
        font-size: 1.1rem;
    }
    
    .image-description {
        font-size: 0.9rem;
    }
    
    .image-content {
        padding: 1.5rem 1rem 1rem;
    }
}

/* === NAVBAR MERGED FROM index.html === */
.navbar {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  z-index: 1000;
  transition: all 0.3s ease;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}
.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}
.nav-logo img { height: 45px; }
.nav-menu { display: flex; list-style: none; gap: 2rem; }
.nav-link {
  color: #ffffff;
  text-decoration: none;
  font-weight: 500;
  transition: all 0.3s ease;
  padding: 8px 16px;
  border-radius: 8px;
}
.nav-link:hover, .nav-link.active {
  color: #4da6ff;
  background: rgba(77, 166, 255, 0.1);
  box-shadow: 0 0 10px rgba(77, 166, 255, 0.2);
}
.hamburger { display: none; flex-direction: column; cursor: pointer; }
.bar { width: 25px; height: 3px; background: #ffffff; margin: 3px 0; transition: 0.3s; }
@media screen and (max-width: 768px) {
  .nav-menu {
    position: fixed;
    left: -100%;
    top: 70px;
    flex-direction: column;
    background: rgba(0, 0, 0, 0.95);
    width: 100%;
    text-align: center;
    transition: 0.3s;
    padding: 20px 0;
  }
  .nav-menu.active { left: 0; }
  .hamburger { display: flex; }
  .hamburger.active .bar:nth-child(2) { opacity: 0; }
  .hamburger.active .bar:nth-child(1) { transform: translateY(8px) rotate(45deg); }
  .hamburger.active .bar:nth-child(3) { transform: translateY(-8px) rotate(-45deg); }
}