#particles-js {
    position: fixed;
    width: 100%;
    height: 100%;
    background: radial-gradient(ellipse at bottom, #1b2735 0%, #090a0f 100%);
    z-index: -1;
  }

/* Hero */
.hero {
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 0 20px;
}

.hero h1 {
  font-size: 3.2em;
  margin-bottom: 10px;
}

.hero p {
  font-size: 1.2em;
  max-width: 600px;
  margin-bottom: 30px;
}

.btn {
  background: linear-gradient(90deg, #36d1dc, #5b86e5);
  padding: 12px 30px;
  border-radius: 30px;
  text-decoration: none;
  color: white;
  font-weight: bold;
  transition: transform 0.3s, box-shadow 0.3s;
}

.btn:hover {
  transform: scale(1.05);
  box-shadow: 0 0 10px #5bc0be;
}

/* 关于区 */
.about, .tech, .services, .fields, .cta {
  padding: 40px 40px;
  text-align: center;
}

.about p {
  max-width: 800px;
  margin: 20px auto;
  font-size: 1.1em;
  color: #ccc;
}

.about h2 {
    font-size: 2.1em;
    margin-bottom: 10px;
  }  


.fields h2 {
    font-size: 2.1em;
    margin-bottom: 10px;
  }  


.learn-more-box {
  margin-top: 18px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.03);
  padding: 18px 22px;
  border-radius: 14px;
  backdrop-filter: blur(8px);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 15px;
  font-size: 0.95rem;
}

.learn-more-box span {
  opacity: 0.85;
}

.learn-more-btn {
  padding: 8px 18px;
  border-radius: 10px;
  border: 1px solid rgba(255,255,255,0.2);
  text-decoration: none;
  font-weight: 500;
  transition: 0.35s ease;
  display: inline-flex;
  align-items: center;
}

.learn-more-btn::after {
  content: "→";
  margin-left: 6px;
  transition: 0.3s ease;
  opacity: 0.6;
}

.learn-more-btn:hover {
  border-color: rgba(255,255,255,0.4);
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(0, 255, 180, 0.18);
}

.learn-more-btn:hover::after {
  margin-left: 10px;
  opacity: 1;
}



/* 视频 */.video-section {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  min-height: 400px;
  padding: 20px;
  margin-bottom:110px;
}

.video-container {
  width: 100%;
  display: flex;
  justify-content: center; /* ⭐ 保证容器内部也居中 */
}

.video-container video {
  width: 70%;
  border-radius: 20px;
  box-shadow: 0 0 30px rgba(91, 192, 190, 0.5);
  display: block;
}

/* 技术应用领域 */
.fields-grid {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
gap: 25px;
margin-top: 50px;
margin-bottom: 130px;
margin-left: 30px;
margin-right: 30px;
}
    
    
.field-card {
background: rgba(255,255,255,0.05);
border-radius: 15px;
padding: 30px;
text-align: center;
transition: 0.3s;
}
    
    
.field-card h3 {
margin-bottom: 20px;
font-size: 21px;
}
    
    
.field-card i {
font-size: 32px;
color: #5bc0be;
margin-bottom: 20px;
display: block;
}
  
.field-card p {
margin-top: 10px;
font-size: 15px;
line-height: 1.4;
}
    
    
.field-card:hover {
transform: translateY(-10px);
background: rgba(255,255,255,0.1);
}

.field-card:hover i {
  transform: scale(1.2);
  transition: 0.3s;
}



/* 技术亮点 */
.tech-grid {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 50px;
  margin-top: 50px;
  margin-bottom: 30px;
}


.tech h2 {
    font-size: 2.1em;
    margin-bottom: 10px;
  }  

.tech h3 {
    margin-bottom: 20px;
    font-size: 21px;
}

.icon-circle {
  width: 80px;
  height: 80px;
  background: radial-gradient(circle, #5bc0be33, #0000);
  border: 2px solid #5bc0be;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 15px auto;
}

.icon-circle i {
  font-size: 32px;
  color: #5bc0be;
}

.tech-item {
  width: 260px;
  background: rgba(255,255,255,0.05);
  padding: 30px;
  border-radius: 15px;
  transition: 0.3s;
}

.tech-item:hover {
  transform: scale(1.05);
  background: rgba(255,255,255,0.1);
}


.service-link {
  color: inherit;
  text-decoration: none;
  font-weight: 500;
  position: relative;
  transition: 0.3s ease;
  padding-bottom: 3px;
}

.service-link::after {
  content: "→";
  position: absolute;
  right: -12px;
  opacity: 0;
  transition: 0.3s ease;
}

.service-link:hover {
  opacity: 0.9;
  letter-spacing: 0.3px;
}

.service-link:hover::after {
  opacity: 1;
  right: -16px;
}

.service-subtext {
  cursor: pointer;
}


/* 服务区 */
/* --- services: alternative style (fixed) --- */
.alt-services {
    text-align: center;
    padding: 120px 5%;
    position: relative;
    overflow: visible;
    color: #e9f6f5;
  }
  
  .alt-services h2 {
    font-size: 2.2rem;
    margin-bottom: 20px;
  }
  
  /* container for three items */
  .service-line {
    display: flex;
    justify-content: center;
    gap: 80px;
    margin-top: 60px;
    align-items: center;
    position: relative;
    flex-wrap: wrap;
  }
  

  /* 每一个服务项 */
  .service-item {
    width: 260px;
    text-align: center;
    position: relative;
    z-index: 2; /* 高于线 */
    transition: transform .28s ease, box-shadow .28s ease;
    padding-top: 18px; /* 给图标圆圈留出空间 */
    box-sizing: border-box;
  }
  
  /* 图标圆圈 — 放在最前面 */
  .service-icon {
    width: 110px;
    height: 110px;
    border-radius: 50%;
    margin: 0 auto 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(91,192,190,0.08);
    border: 2px solid rgba(91,192,190,0.18);
    box-shadow: 0 6px 24px rgba(11,26,30,0.45);
    transition: transform .28s ease, box-shadow .28s ease, border-color .28s ease;
    position: relative;
  }
  
  /* icon 本身的尺寸/颜色 */
  .service-icon i {
    font-size: 40px;
    color: #5bc0be;
  }
  
  /* 小发光环（伪元素） */
  .service-icon::after {
    content: "";
    position: absolute;
    inset: -10px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(91,192,190,0.18), rgba(91,192,190,0));
    filter: blur(6px);
    opacity: 0;
    transition: opacity .28s ease, transform .28s ease;
    z-index: -1;
  }
  
  /* hover / focus 效果 */

  .service-item:hover {
    transform: translateY(-8px) scale(1.02);
  }
  
  .service-subtext {
    margin-top: 30px;
    color: #5bc0be;
    opacity: .85;
  }
  

  .service-item:hover .service-icon {
    transform: scale(1.06);
    border-color: rgba(91,192,190,0.7);
    box-shadow: 0 12px 40px rgba(91,192,190,0.18);
  }
  .service-item:hover .service-icon::after {
    opacity: 1;
    transform: scale(1.02);
  }
  
  /* 标题与文字 */
  .service-item h3 {
    margin: 12px 0 8px;
    font-size: 20px;
    color: #dff7f6;
  }
  .service-item p {
    color: rgba(223,247,246,0.85);
    line-height: 1.5;
    margin: 0 auto;
    max-width: 240px;
  }
  
  /* 底部短线（hover 扩展） */
  .service-item::after {
    content: "";
    display: block;
    width: 36%;
    height: 3px;
    background: rgba(91,192,190,0.0);
    margin: 14px auto 0;
    border-radius: 6px;
    transition: width .28s ease, background .28s ease;
  }
  .service-item:hover::after {
    width: 56%;
    background: #5bc0be;
  }
  
  /* 小屏幕优化 — 隐藏横线并垂直堆叠 */
  @media (max-width: 880px) {
    .service-line::before {
      display: none;
    }
    .service-line {
      gap: 28px;
      flex-direction: column;
      align-items: center;
    }
    .service-item {
      width: 82%;
      padding-top: 10px;
    }
    .service-icon {
      width: 92px;
      height: 92px;
    }
  }
  

/* 响应式 */
@media (max-width: 768px) {
  .nav-links { display: none; }
  .video-container video { width: 90%; }
  .tech-grid, .service-cards { flex-direction: column; align-items: center; }
  .hero h1 { font-size: 1.8em; }
}