/* ===== 千讯科技企业官网 — 白底简洁企业风 ===== */
:root {
  --bg-white: #FFFFFF;
  --bg-light: #F7F9FC;
  --text-dark: #333333;
  --text-body: #666666;
  --text-muted: #999999;
  --brand-primary: #2B7CD8;
  --brand-hover: #1E5FA8;
  --border-color: #E8EDF3;
  --radius-sm: 4px;
  --radius-md: 8px;
  --shadow-card: 0 2px 12px rgba(0, 0, 0, 0.06);
  --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.1);
  --font-family: -apple-system, BlinkMacSystemFont, 'PingFang SC',
                 'Microsoft YaHei', 'Segoe UI', Roboto, sans-serif;
  --transition: all 0.3s ease;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  font-family: var(--font-family);
  background: var(--bg-white);
  color: var(--text-body);
  line-height: 1.6;
  font-size: 14px;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
img { max-width: 100%; height: auto; display: block; }

/* ===== 导航栏 ===== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: var(--bg-white);
  border-bottom: 1px solid var(--border-color);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.04);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 70px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-img {
  height: 40px;
  width: auto;
  display: block;
}

.logo-text {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-dark);
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: 0;
}

.nav-link {
  display: inline-block;
  padding: 0 20px;
  font-size: 15px;
  color: var(--text-dark);
  line-height: 70px;
  position: relative;
  font-weight: 400;
}

.nav-link:hover,
.nav-link.active {
  color: var(--brand-primary);
}

.nav-link.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 20px;
  right: 20px;
  height: 2px;
  background: var(--brand-primary);
}

/* 汉堡菜单 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 44px; height: 44px;
  background: transparent;
  border: none;
  cursor: pointer;
}

.hamburger-line {
  display: block;
  width: 22px; height: 2px;
  background: var(--text-dark);
  border-radius: 2px;
  transition: var(--transition);
}

/* ===== 导航下拉菜单 ===== */
.nav-dropdown {
  position: relative;
  display: inline-flex;
  align-items: center;
}

.nav-dropdown .nav-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.dropdown-arrow {
  width: 14px;
  height: 14px;
  stroke: var(--text-muted);
  transition: transform 0.3s ease;
}

.nav-dropdown:hover .dropdown-arrow {
  transform: rotate(180deg);
  stroke: var(--brand-primary);
}

.dropdown-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  min-width: 180px;
  background: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  box-shadow: 0 6px 24px rgba(0, 0, 0, 0.1);
  padding: 8px 0;
  opacity: 0;
  visibility: hidden;
  transform: translateX(-50%) translateY(8px);
  transition: opacity 0.25s ease, transform 0.25s ease, visibility 0.25s ease;
  z-index: 1001;
}

.nav-dropdown:hover .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.dropdown-item {
  display: block;
  padding: 10px 20px;
  font-size: 14px;
  color: var(--text-body);
  white-space: nowrap;
  transition: var(--transition);
}

.dropdown-item:hover {
  background: var(--bg-light);
  color: var(--brand-primary);
}

/* ===== Banner 全屏轮播 ===== */
.banner {
  margin-top: 70px;
  width: 100%;
  height: calc(100vh - 70px);
  overflow: hidden;
  position: relative;
}

.banner-slider {
  position: relative;
  width: 100%;
  height: 100%;
}

.banner-track {
  width: 100%;
  height: 100%;
  position: relative;
}

.banner-slide {
  position: absolute;
  inset: 0;
  opacity: 0;
  transition: opacity 0.8s ease;
}

.banner-slide.active {
  opacity: 1;
}

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

/* 左右箭头 */
.banner-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  width: 48px;
  height: 48px;
  background: rgba(255, 255, 255, 0.25);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
  z-index: 10;
}

.banner-arrow:hover {
  background: rgba(255, 255, 255, 0.6);
}

.banner-arrow svg {
  width: 24px;
  height: 24px;
  stroke: #FFFFFF;
}

.banner-arrow:hover svg {
  stroke: var(--text-dark);
}

.banner-arrow-left {
  left: 24px;
}

.banner-arrow-right {
  right: 24px;
}

/* 指示点 */
.banner-dots {
  position: absolute;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 10px;
  z-index: 10;
}

.banner-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.8);
  background: transparent;
  cursor: pointer;
  transition: var(--transition);
  padding: 0;
}

.banner-dot.active {
  background: #FFFFFF;
  border-color: #FFFFFF;
}

.banner-dot:hover {
  background: rgba(255, 255, 255, 0.6);
}

/* ===== 通用 Section ===== */
.section-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section-header {
  text-align: center;
  margin-bottom: 50px;
}

.section-title {
  font-size: 28px;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 8px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 40px;
  height: 2px;
  background: var(--brand-primary);
}

.section-subtitle-en {
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 2px;
  margin-top: 16px;
  text-transform: uppercase;
}

/* ===== 产品与服务 — 卡片网格 ===== */
.services {
  padding: 80px 0;
  background: var(--bg-white);
}

.services-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.service-card {
  text-align: center;
  padding: 32px 20px;
  background: var(--bg-white);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  transition: var(--transition);
}

.service-card:hover {
  box-shadow: var(--shadow-hover);
  border-color: var(--brand-primary);
  transform: translateY(-4px);
}

.service-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-light);
  border-radius: 50%;
}

.service-icon svg {
  width: 28px;
  height: 28px;
  stroke: var(--brand-primary);
}

.service-name {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-dark);
  margin-bottom: 12px;
}

.service-desc {
  font-size: 13px;
  color: var(--text-body);
  line-height: 1.8;
}

/* ===== 公司动态 ===== */
.news {
  padding: 80px 0;
  background: var(--bg-light);
}

.news-content {
  display: grid;
  grid-template-columns: 380px 1fr;
  gap: 40px;
  align-items: start;
}

.news-featured {
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.news-featured-img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

.news-featured-caption {
  padding: 16px;
  font-size: 14px;
  color: var(--text-body);
  background: var(--bg-white);
  text-align: center;
}

.news-list {
  display: flex;
  flex-direction: column;
}

.news-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 0;
  border-bottom: 1px solid var(--border-color);
}

.news-item:first-child {
  padding-top: 0;
}

.news-item-content {
  flex: 1;
  min-width: 0;
}

.news-item-title {
  font-size: 14px;
  font-weight: 400;
  color: var(--text-dark);
  margin-bottom: 4px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.news-item-title.highlight {
  color: var(--brand-primary);
  font-weight: 500;
}

.news-item-desc {
  font-size: 12px;
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.news-item-date {
  font-size: 13px;
  color: var(--text-muted);
  white-space: nowrap;
  margin-left: 24px;
}

.news-more {
  display: inline-block;
  margin-top: 16px;
  font-size: 13px;
  color: var(--text-muted);
  text-align: right;
}

.news-more:hover {
  color: var(--brand-primary);
}

/* ===== 底部 ===== */
.footer {
  padding: 32px 0;
  background: #2C3E50;
  color: rgba(255, 255, 255, 0.7);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  text-align: center;
}

.footer-top {
  margin-bottom: 16px;
}

.footer-links {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.footer-links a {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.7);
  padding: 4px 8px;
}

.footer-links a:hover {
  color: #FFFFFF;
}

.footer-divider {
  color: rgba(255, 255, 255, 0.3);
  font-size: 12px;
}

.footer-info p {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
  line-height: 2;
}

/* ===== 滚动淡入动画 ===== */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== 响应式 ===== */
@media (max-width: 1023px) {
  .services-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  .news-content {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 767px) {
  .nav-links { display: none; }
  .nav-links.active {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%; left: 0; right: 0;
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-color);
    padding: 16px 24px;
    gap: 0;
    box-shadow: var(--shadow-card);
  }
  .nav-links.active .nav-link {
    line-height: 48px;
    padding: 0 12px;
  }
  .nav-toggle { display: flex; }

  .banner { height: 60vh; }

  .services-grid {
    grid-template-columns: 1fr;
  }

  .news-content {
    grid-template-columns: 1fr;
  }

  .section-title { font-size: 22px; }
}

@media (max-width: 480px) {
  .nav-container { padding: 0 16px; }
  .section-container { padding: 0 16px; }
  .banner { height: 45vh; }
}

/* ===== prefers-reduced-motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
  .fade-in { opacity: 1; transform: none; }
}