* { box-sizing:border-box; margin:0; padding:0; }
html { scroll-behavior:smooth; }
body { font-family:Arial, sans-serif; background:#f8f8f8; color:#333; line-height:1.6; }

/* 语言选择器样式 */
.language-selector {
  margin-left:auto;
  margin-right: 20px;
  z-index: 100;
}

#lang-select {
  background-color: #f8f9fa;
  color: #1f2d3d;
  border: 1px solid #ddd;
  padding: 8px 12px;
  border-radius: 5px;
  font-size: 0.9em;
  cursor: pointer;
  transition: all 0.3s ease;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%23333' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 8px center;
  padding-right: 30px;
}

#lang-select:hover {
  border-color: #ffcc00;
  background-color: #fff;
}

#lang-select:focus {
  outline: none;
  border-color: #5a3d9e;
  box-shadow: 0 0 0 2px rgba(90, 61, 158, 0.2);
}

header { position:fixed; top:0; width:100%; z-index:100; background:#1f2d3d; transition:top 0.3s; box-shadow:0 2px 6px rgba(0,0,0,0.2); height:80px;}
.header-container { display:flex; justify-content:flex-start; align-items:center; width:100%; padding:15px 20px; height:100%; }
.header-container nav { margin-left:auto; margin-right:50px; }
.logo img { height:60px; }
nav { display:flex; align-items:center; }
nav a { color:#fff; text-decoration:none; margin-left:35px; font-weight:bold; transition:color 0.3s; }
nav a:first-child { margin-left:0; }
nav a:hover { color:#ffcc00; }

.banner { margin-top:80px; width:100%; height:400px; overflow:hidden; }
.banner img { width:100%; height:100%; object-fit:cover; }

/* 业务介绍区域 */
.business-intro {
  background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
  padding: 50px 0;
  border-bottom: 1px solid #ddd;
}

.intro-content {
  text-align: center;
  max-width: 1000px;
  margin: 0 auto;
}

.intro-content h2 {
  font-size: 2.5em;
  color: #1f2d3d;
  margin-bottom: 25px;
  font-weight: 700;
  text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.intro-content p {
  font-size: 1.2em;
  color: #555;
  line-height: 1.7;
  margin-bottom: 40px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.service-highlights {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 25px;
  margin-top: 30px;
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
}

.highlight {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
  font-weight: 600;
  padding: 18px 25px;
  font-size: 1.1em;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.3);
  transition: all 0.3s ease;
  text-align: center;
  white-space: nowrap;
}

.highlight:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.container { max-width:1000px; margin:30px auto; padding:0 20px; }

h2 { font-size:1.8em; color:#1f2d3d; margin-bottom:15px; scroll-margin-top:80px; }
.service-section { margin-bottom:50px; }

.row-layout { display:flex; flex-wrap:nowrap; gap:30px; align-items:stretch; }
.row-layout .carousel, .row-layout .about-img { flex:1 1 45%; max-width:45%; }
.row-layout .service-text, .row-layout .about-text { flex:1 1 55%; max-width:55%; }

/* 反向布局 - 文字在左，图片在右 */
.row-layout.row-reverse { flex-direction:row; }
.row-layout.row-reverse .service-text { order:1; }
.row-layout.row-reverse .carousel { order:2; }

/* About Us 优化样式 */
.row-layout .about-img-small { flex:1 1 20%; max-width:20%; }
.row-layout .about-img-small img { width:100%; height:auto; max-height:250px; object-fit:cover; border-radius:8px; }
.row-layout .about-text-expanded { flex:1 1 75%; max-width:75%; }

.carousel { position:relative; width:100%; overflow:hidden; border-radius:8px; min-height:300px; }
.carousel img { width:100%; height:300px; display:none; border-radius:8px; object-fit:cover; }
.carousel img.active { display:block; }
.carousel .prev, .carousel .next {
  cursor:pointer;
  position:absolute;
  top:50%;
  transform:translateY(-50%);
  color:white;
  font-size:2em;
  font-weight:bold;
  padding:5px 10px;
  background:rgba(0,0,0,0.3);
  border-radius:50%;
  user-select:none;
}
.carousel .prev { left:10px; }
.carousel .next { right:10px; }

.service-video { margin-top:15px; text-align:center; }
.service-video video { width:60%; max-width:100%; border-radius:8px; }

.service-text { 
  display:flex; 
  flex-direction:column; 
  justify-content:center; 
  padding:20px; 
}

.service-button { margin-top:20px; }
.quote-btn { 
  display:inline-block; 
  background:#1f2d3d; 
  color:#fff; 
  padding:12px 24px; 
  border-radius:5px; 
  text-decoration:none; 
  font-weight:bold; 
  transition:background 0.3s;
}
.quote-btn:hover { background:#2a3a4a; }

/* 视频展示区域 */
.video-showcase {
  background: #f9f9f9;
  padding: 50px 0;
  margin-bottom: 30px;
}

.video-showcase h2 {
  text-align: center;
  margin-bottom: 40px;
  font-size: 2.2em;
  color: #1f2d3d;
}

.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
  gap: 40px;
  max-width: 1000px;
  margin: 0 auto;
}

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

.video-item h3 {
  margin-bottom: 15px;
  font-size: 1.4em;
  color: #1f2d3d;
}

.video-item video {
  width: 100%;
  max-width: 100%;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.contact-form input, .contact-form textarea, .contact-form button {
  width:100%; padding:10px; margin-bottom:15px; border-radius:5px; border:1px solid #ccc; font-size:1em;
}
.contact-form button { background:#5a3d9e; color:#fff; border:none; cursor:pointer; }
.contact-form button:hover { background:#472c7a; }

footer { background:#1f2d3d; color:#fff; text-align:center; padding:20px 0; margin-top:30px; }

@media(max-width:768px){
  .header-container {
    flex-wrap: wrap;
    height: auto;
    padding: 10px 15px;
  }
  
  .language-selector {
    margin-left: auto;
    margin-right: 15px;
    margin-bottom: 10px;
  }
  
  .intro-content h2 {
    font-size: 2em;
  }
  
  .intro-content p {
    font-size: 1.1em;
    text-align: center;
  }
  
  .service-highlights {
    grid-template-columns: 1fr;
    gap: 15px;
  }
  
  .highlight {
    padding: 15px 20px;
    font-size: 1em;
    white-space: normal;
  }
  
  .video-grid {
    grid-template-columns: 1fr;
    gap: 30px;
  }
  
  .video-showcase {
    padding: 30px 0;
  }
  
  .video-showcase h2 {
    font-size: 1.8em;
  }
  
  .row-layout { flex-direction:column; flex-wrap:wrap; }
  .row-layout.row-reverse { flex-direction:column; }
  .row-layout .carousel, .row-layout .service-text, .row-layout .about-img, .row-layout .about-text,
  .row-layout .about-img-small, .row-layout .about-text-expanded { max-width:100%; order:unset; }
  .service-text { padding:10px; }
  .carousel img { max-height:250px; }
  .logo { margin-bottom:10px; }
  nav { flex-wrap:wrap; justify-content:center; }
  nav a { margin:5px 10px; }
}
/* 两列布局容器 */
.two-column-section {
  display: flex;
  gap: 30px;
  margin: 50px 0;
  padding: 20px;
}

/* 列通用样式 */
.column {
  flex: 1;
  min-width: 0; /* 防止内容溢出 */
}

/* FAQ列样式 */
.faq-column {
  padding: 20px;
  background-color: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

/* FAQ基础样式（简化版，保持与网站风格统一） */
.faq-item {
  margin-bottom: 10px;
  border: 1px solid #eee;
  border-radius: 5px;
  overflow: hidden;
}

.faq-question {
  width: 100%;
  background-color: #f8f9fa;
  color: #1f2d3d;
  padding: 12px 15px;
  text-align: left;
  border: none;
  outline: none;
  font-size: 1em;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.faq-question:after {
  content: "+";
  font-size: 1.2em;
  color: #5a3d9e;
}

.faq-question.active:after {
  content: "-";
}

.faq-answer {
  padding: 0 15px;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease, padding 0.3s ease;
}

.faq-answer p {
  color: #555;
  line-height: 1.6;
  padding: 15px 0;
}

.faq-answer.active {
  max-height: 300px;
}

/* 联系表单列样式 */
.contact-column {
  padding: 20px;
  background-color: #fff;
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.05);
}

/* 响应式调整 */
@media(max-width:768px) {
  .two-column-section {
    flex-direction: column;
    gap: 20px;
    margin: 30px 0;
    padding: 10px;
  }
  
  .faq-column, .contact-column {
    padding: 15px;
  }
}