/* =========================================================
   丽清源天津官网 - 响应式样式表
   ========================================================= */

/* ===== 大屏 (≥1200px) ===== */
@media (max-width: 1400px) {
  .header-logo img {
    width: 350px;
    height: auto;
  }

  .nav-menu > li > a {
    padding: 0 15px;
    font-size: 14px;
  }

  .search-box {
    width: 160px;
  }
}

@media (max-width: 1200px) {
  .header-logo img {
    width: 300px;
  }

  .nav-menu > li > a {
    padding: 0 12px;
    font-size: 13px;
  }

  .footer-logo img {
    width: 380px;
    height: auto;
  }

  .footer-menu a {
    padding: 8px 20px;
    min-width: 120px;
    font-size: 13px;
  }
}

/* ===== 平板 (≤992px) ===== */
@media (max-width: 992px) {
  /* ----- 核心技术区域 ----- */
  .core-tech {
    min-height: auto;
    padding: 0;
    display: block;
  }

  .core-tech .container:first-of-type {
    position: relative;
    z-index: 2;
    padding-top: 120px;
    padding-bottom: 40px;
  }

  .core-tech .container:last-of-type {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
  }

  .tech-header {
    margin-bottom: 40px;
  }

  .tech-title {
    font-size: 28px;
  }

  .tech-grid {
    gap: 20px;
    margin-top: 20px;
  }

  .tech-grid-row {
    gap: 30px;
  }

  .tech-grid-row:first-child {
    transform: none;
  }

  .tech-grid-row:nth-child(2) {
    transform: none;
    gap: 380px;
    margin-top: 90px;
  }

  .tech-grid-row:nth-child(3) {
    transform: none;
    gap: 160px;
    margin-top: 30px;
  }

  .tech-item {
    flex: 0 0 auto;
  }

  .tech-icon {
    height: 80px;
  }

  .tech-icon img {
    height: 100%;
    width: auto;
  }

  .tech-subtitle {
    font-size: 16px;
  }

  /* 平板端新闻列表1列 */
  .news-list {
    grid-template-columns: 1fr;
  }
  .header .container {
    height: 70px;
  }

  .header-logo img {
    width: 250px;
    height: auto;
  }

  .nav-menu,
  .header-search {
    display: none;
  }

  .mobile-menu-btn {
    display: flex;
  }

  .mobile-nav-overlay {
    display: block;
  }

  .top-bar-left span {
    font-size: 12px;
  }

  .top-bar-right span {
    font-size: 12px;
  }

  .footer-logo img {
    width: 320px;
  }

  .footer-menu {
    gap: 10px;
  }

  .footer-menu a {
    padding: 8px 18px;
    min-width: 100px;
    font-size: 13px;
  }
}

/* ===== 手机 (≤768px) ===== */
@media (max-width: 768px) {
  /* ----- 公司介绍区域：手机端隐藏图片，文字占满 ----- */
  .company-intro .col-lg-6.company-intro-img {
    display: none;
  }

  .company-intro .col-lg-6.company-intro-text {
    flex: 0 0 100%;
    max-width: 100%;
    padding-right: 0;
  }

  /* ----- 核心技术区域 ----- */
  .core-tech {
    padding: 0;
    display: block;
  }

  .core-tech .container:first-of-type {
    padding-top: 100px;
    padding-bottom: 30px;
  }

  /* 手机端新闻列表1列 */
  .news-list {
    grid-template-columns: 1fr;
  }

  /* 手机端隐藏核心技术标题、英文副标题和分隔线，但保持空间 */
  .core-tech .tech-title,
  .core-tech .tech-en-title,
  .core-tech .tech-divider {
    visibility: hidden;
  }

  .tech-header {
    margin-bottom: 30px;
  }

  .tech-title {
    font-size: 24px;
  }

  .tech-en-title {
    font-size: 12px;
  }

  .tech-subtitle {
    font-size: 15px;
  }

  .tech-slogan {
    font-size: 13px;
  }

  .tech-grid {
    gap: 15px;
    margin-top: 10px;
  }

  .tech-grid-row {
    gap: 20px;
  }

  .tech-grid-row:nth-child(2) {
    gap: 300px;
  }

  .tech-grid-row:nth-child(3) {
    gap: 130px;
  }
  


  .tech-icon {
    height: 65px;
  }

  .tech-link-btn {
    font-size: 14px;
    padding: 8px 28px;
  }
  .top-bar {
    height: auto;
    line-height: 1.4;
    padding: 8px 0;
  }

  .top-bar .container {
    flex-direction: column;
    gap: 4px;
  }

  .header .container {
    height: 60px;
    padding: 0 15px;
  }

  .header-logo img {
    width: 200px;
    height: auto;
  }

  .mobile-menu-btn {
    width: 32px;
    height: 32px;
    gap: 4px;
    padding: 5px 4px;
  }

  .mobile-menu-btn span {
    width: 18px;
    height: 2px;
  }

  .footer {
    padding: 50px 0 20px;
  }

  .footer-logo {
    margin-bottom: 30px;
  }

  .footer-logo img {
    width: 260px;
  }

  .footer-menu {
    flex-direction: column;
    align-items: center;
    gap: 10px;
    margin-bottom: 30px;
  }

  .footer-menu a {
    width: 200px;
    text-align: center;
  }

  .footer-social {
    gap: 15px;
  }

  .footer-social a {
    width: 38px;
    height: 38px;
  }

  .back-to-top {
    bottom: 15px;
    right: 15px;
    width: 38px;
    height: 38px;
    font-size: 16px;
  }
}

/* ===== 小屏手机 (≤480px) ===== */
@media (max-width: 480px) {
  /* ----- 核心技术区域 ----- */
  .core-tech {
    padding: 0;
	min-height:360px;
  }

  .core-tech .container:first-of-type {
    padding-top: 30px;
    padding-bottom: 20px;
  }

  .tech-title {
    font-size: 20px;
  }

  .tech-icon {
    height: 50px;
  }
  .header-logo img {
    width: 160px;
  }

  .top-bar-left span,
  .top-bar-right span {
    font-size: 11px;
  }

  .top-bar-left .top-icon {
    width: 14px;
    height: 14px;
  }

  .top-bar-right .top-icon {
    width: 14px;
    height: 14px;
  }

  .mobile-nav {
    width: 260px;
  }

  .footer-logo img {
    width: 220px;
  }

  .footer-menu a {
    width: 180px;
    font-size: 12px;
  }
  

  .tech-grid-row:nth-child(2) {
    gap: 260px;
	margin-top: 64px;
  }

  .tech-grid-row:nth-child(3) {
    gap: 120px;
	margin-top: 64px;
  }
}