html {
    scroll-behavior: smooth;
  }

  .kl-support-page {
    width: 100%;
    background: #fff;
    font-family: Arial, Helvetica, sans-serif;
    color: #111;
  }

  .kl-hero {
    width: 100%;
    padding: 70px 24px 60px;
    box-sizing: border-box;
  }

  .kl-hero-container {
    max-width: 1120px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 480px 1fr;
    gap: 90px;
    align-items: start;
  }

  .kl-gallery-main {
    width: 480px;
    height: 480px;
    background: #f4f4f4;
    border-radius: 8px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .kl-main-product-img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
  }

  .kl-product-info h1 {
    margin: 0 0 34px;
    font-size: 38px;
    line-height: 1.1;
    font-weight: 700;
    color: #000;
    letter-spacing: -1px;
    text-transform: uppercase;
  }

  .kl-sold-date {
    margin: 0 0 16px;
    font-size: 15px;
    color: #777;
  }

  .kl-product-desc {
    margin: 0 0 22px;
    font-size: 17px;
    line-height: 1.55;
    color: #111;
  }

  .kl-card-grid {
    margin-top: 28px;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  .kl-card {
    position: relative;
    height: 120px;
    padding: 18px 16px;
    background: #f4f5f6;
    border-radius: 5px;
    text-decoration: none;
    color: #111;
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: all 0.25s ease;
  }

  .kl-card:hover {
    background: #eceeef;
    transform: translateY(-2px);
  }

  .kl-card-icon {
    width: 32px;
    height: 32px;
    color: #000;
  }

  .kl-card-icon svg {
    width: 32px;
    height: 32px;
    stroke: currentColor;
  }

  .kl-card-title {
    font-size: 18px;
    line-height: 1.2;
    font-weight: 400;
    color: #111;
  }

  .kl-card-arrow {
    position: absolute;
    right: 16px;
    bottom: 16px;
    width: 36px;
    height: 36px;
    background: #d8dadd;
    border-radius: 50%;
  }

  .kl-card-arrow::after {
    content: "";
    position: absolute;
    left: 12px;
    top: 9px;
    width: 11px;
    height: 11px;
    border-right: 2px solid #fff;
    border-bottom: 2px solid #fff;
    transform: rotate(45deg);
  }

  .kl-section {
    max-width: 1120px;
    margin: 0 auto;
    padding: 76px 24px;
    border-top: 1px solid #eee;
    box-sizing: border-box;
    scroll-margin-top: 80px;
  }

  .kl-section h2 {
    margin: 0 0 42px;
    font-size: 36px;
    line-height: 1.2;
    color: #000;
    font-weight: 700;
  }

  .kl-section p,
  .kl-section li {
    font-size: 16px;
    line-height: 1.7;
    color: #333;
  }

  .kl-video-wrap {
    width: 100%;
    background: #f4f4f4;
    border-radius: 10px;
    overflow: hidden;
  }

  .kl-video-wrap video {
    width: 100%;
    display: block;
  }

  .kl-user-guide-layout {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 50px;
    align-items: center;
  }

  .kl-pdf-card {
    width: 150px;
    height: 150px;
    border: 1px solid #cfcfcf;
    background: #fff;
    position: relative;
    box-sizing: border-box;
  }

  .kl-pdf-card::before {
    content: "";
    position: absolute;
    right: -1px;
    top: -1px;
    width: 48px;
    height: 48px;
    background: linear-gradient(45deg, #f4f4f4 0%, #f4f4f4 50%, #fff 50%, #fff 100%);
    border-left: 1px solid #cfcfcf;
    border-bottom: 1px solid #cfcfcf;
  }

  .kl-pdf-thumb-img {
    position: absolute;
    left: 35px;
    top: 50px;
    width: 78px;
    height: 45px;
    object-fit: contain;
  }

  .kl-pdf-bottom {
    position: absolute;
    left: 0;
    bottom: 0;
    width: 100%;
    height: 32px;
    background: #efefef;
    border-top: 1px solid #ddd;
    box-sizing: border-box;
  }

  .kl-pdf-label {
    position: absolute;
    right: 10px;
    bottom: 8px;
    font-size: 12px;
    color: #666;
  }

  .kl-user-guide-info h3 {
    margin: 0 0 20px;
    font-size: 20px;
    line-height: 1.3;
    color: #000;
    font-weight: 700;
  }

  .kl-guide-date {
    margin: 0 0 16px;
    color: #777;
    font-size: 16px;
  }

  .kl-guide-file-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin: 0 0 28px;
  }

  .kl-guide-file-icon {
    width: 24px;
    height: 24px;
    flex: 0 0 auto;
  }

  .kl-guide-file-link {
    font-size: 16px;
    color: #111;
    text-decoration: underline;
  }

  .kl-download-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 260px;
    height: 44px;
    padding: 0 26px;
    background: #050505;
    color: #fff;
    border-radius: 3px;
    text-decoration: none;
    font-size: 16px;
    font-weight: 700;
    box-sizing: border-box;
  }

  .kl-download-btn:hover {
    background: #222;
  }

  .kl-faq-module {
    width: 100%;
    max-width: 1120px;
    margin: 0 auto;
    padding: 76px 24px;
    box-sizing: border-box;
    font-family: Arial, Helvetica, sans-serif;
    color: #111;
    background: #fff;
    border-top: 1px solid #eee;
    scroll-margin-top: 80px;
  }

  .kl-faq-layout {
    width: 100%;
    display: grid;
    grid-template-columns: 300px minmax(0, 1fr);
    column-gap: 48px;
    align-items: start;
  }

  .kl-faq-sidebar {
    position: sticky;
    top: 80px;
    padding: 0 34px 0 0;
    border-right: 1px solid #dcdcdc;
    box-sizing: border-box;
  }

  .kl-faq-title {
    margin: 0 0 34px;
    font-size: 32px;
    line-height: 1.15;
    font-weight: 700;
    color: #000;
  }

  .kl-faq-tabs {
    display: grid;
    gap: 18px;
  }

  .kl-faq-tab {
    display: block;
    width: 100%;
    border: 0;
    padding: 0;
    margin: 0;
    background: transparent;
    text-align: left;
    font-size: 15px;
    line-height: 1.35;
    font-weight: 700;
    color: #b8b8b8;
    cursor: pointer;
    transition: color 0.2s ease;
  }

  .kl-faq-tab:hover,
  .kl-faq-tab.active {
    color: #111;
  }

  .kl-faq-content {
    width: 100%;
    max-height: 560px;
    overflow-y: auto;
    padding: 0 18px 0 0;
    box-sizing: border-box;
  }

  .kl-faq-content::-webkit-scrollbar {
    width: 5px;
  }

  .kl-faq-content::-webkit-scrollbar-track {
    background: #f1f1f1;
  }

  .kl-faq-content::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 10px;
  }

  .kl-faq-group {
    display: none;
    width: 100%;
  }

  .kl-faq-group.active {
    display: block;
  }

  .kl-faq-item {
    width: 100%;
    border-bottom: 1px solid #d8d8d8;
    box-sizing: border-box;
  }

  .kl-faq-question {
    position: relative;
    width: 100%;
    padding: 20px 36px 20px 0;
    box-sizing: border-box;
    border: 0;
    background: transparent;
    text-align: left;
    cursor: pointer;
    font-size: 17px;
    line-height: 1.45;
    font-weight: 700;
    color: #444;
  }

  .kl-faq-question::after {
    content: "";
    position: absolute;
    right: 4px;
    top: 50%;
    width: 8px;
    height: 8px;
    border-right: 1.8px solid #555;
    border-bottom: 1.8px solid #555;
    transform: translateY(-65%) rotate(45deg);
    transition: transform 0.28s ease;
  }

  .kl-faq-item.open .kl-faq-question::after {
    transform: translateY(-35%) rotate(225deg);
  }

  /* FAQ 展开动画：使用真实高度 height 过渡，比 max-height 更丝滑 */
  .kl-faq-answer {
    height: 0;
    overflow: hidden;
    opacity: 0;
    transform: translateY(-6px);
    transition:
      height 0.46s cubic-bezier(0.22, 1, 0.36, 1),
      opacity 0.26s ease,
      transform 0.46s cubic-bezier(0.22, 1, 0.36, 1);
    will-change: height, opacity, transform;
  }

  .kl-faq-item.open .kl-faq-answer {
    opacity: 1;
    transform: translateY(0);
  }

  .kl-faq-answer-inner {
    padding: 0 36px 24px 0;
    box-sizing: border-box;
  }

  .kl-faq-answer p,
  .kl-faq-answer li {
    font-size: 15px;
    line-height: 1.7;
    color: #555;
  }

  .kl-faq-answer p {
    margin: 0 0 12px;
  }

  .kl-faq-answer ul,
  .kl-faq-answer ol {
    margin: 8px 0 12px;
    padding-left: 22px;
  }

  .kl-contact-section {
    width: 100%;
    background: #f3f4f5;
    padding: 76px 24px;
    box-sizing: border-box;
    border-top: 1px solid #eee;
    scroll-margin-top: 80px;
  }

  .kl-contact-inner {
    max-width: 1120px;
    margin: 0 auto;
  }

  .kl-contact-section h2 {
    margin: 0 0 42px;
    text-align: center;
    font-size: 36px;
    line-height: 1.2;
    color: #000;
    font-weight: 700;
  }

  .kl-contact-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
  }

  .kl-contact-card {
    background: #fff;
    border-radius: 4px;
    padding: 34px 32px;
    min-height: 230px;
    box-sizing: border-box;
  }

  .kl-contact-card h3 {
    margin: 0 0 22px;
    font-size: 24px;
    line-height: 1.25;
    color: #000;
    font-weight: 700;
  }

  .kl-contact-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 40px;
    padding: 0 18px;
    margin: 0 0 24px;
    border: 1px solid #111;
    border-radius: 3px;
    background: #fff;
    color: #111;
    text-decoration: none;
    font-size: 15px;
    font-weight: 700;
    box-sizing: border-box;
  }

  .kl-contact-btn.black {
    background: #050505;
    color: #fff;
  }

  .kl-contact-link {
    display: inline-block;
    margin: 0 0 24px;
    color: #111;
    text-decoration: underline;
    font-size: 16px;
    line-height: 1.5;
  }

  .kl-contact-card p {
    margin: 0;
    font-size: 16px;
    line-height: 1.6;
    color: #222;
  }

  @media (max-width: 900px) {
    .kl-hero {
      padding: 40px 16px;
    }

    .kl-hero-container {
      grid-template-columns: 1fr;
      gap: 40px;
    }

    .kl-gallery-main {
      width: 100%;
      height: auto;
      aspect-ratio: 1 / 1;
    }

    .kl-product-info h1 {
      font-size: 32px;
    }

    .kl-card-grid {
      grid-template-columns: 1fr;
      gap: 16px;
    }

    .kl-section {
      padding: 54px 16px;
    }

    .kl-section h2 {
      font-size: 28px;
      margin-bottom: 28px;
    }

    .kl-user-guide-layout {
      grid-template-columns: 1fr;
      gap: 28px;
    }

    .kl-pdf-card {
      width: 150px;
      height: 150px;
    }

    .kl-download-btn {
      min-width: 100%;
    }

    .kl-faq-module {
      padding: 0 0 54px;
      max-width: none;
      width: 100%;
      border-top: 1px solid #eee;
      scroll-margin-top: 0;
    }

    .kl-faq-layout {
      display: block;
      width: 100%;
    }

    .kl-faq-sidebar {
      position: sticky;
      top: 0;
      z-index: 50;
      background: #fff;
      padding: 28px 16px 0;
      border-right: 0;
      border-bottom: 1px solid #dcdcdc;
      box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
    }

    .kl-faq-title {
      font-size: 32px;
      margin: 0 0 24px;
      line-height: 1.15;
    }

    .kl-faq-tabs {
      display: flex;
      gap: 34px;
      overflow-x: auto;
      overflow-y: hidden;
      white-space: nowrap;
      padding: 0 0 12px;
      scrollbar-width: none;
      -webkit-overflow-scrolling: touch;
    }

    .kl-faq-tabs::-webkit-scrollbar {
      display: none;
    }

    .kl-faq-tab {
      width: auto;
      flex: 0 0 auto;
      white-space: nowrap;
      font-size: 18px;
      line-height: 1.3;
      font-weight: 500;
      color: #111;
      padding: 0 0 14px;
      position: relative;
    }

    .kl-faq-tab.active::after {
      content: "";
      position: absolute;
      left: 0;
      right: 0;
      bottom: -13px;
      height: 4px;
      background: #ff6a2a;
    }

    .kl-faq-content {
      max-height: none;
      overflow: visible;
      padding: 28px 16px 0;
      width: 100%;
      box-sizing: border-box;
    }

    .kl-faq-question {
      font-size: 18px;
      line-height: 1.45;
      font-weight: 600;
      padding: 24px 34px 24px 0;
    }

    .kl-faq-answer-inner {
      padding: 0 34px 24px 0;
    }

    .kl-faq-answer p,
    .kl-faq-answer li {
      font-size: 15px;
      line-height: 1.7;
    }

    .kl-contact-section {
      padding: 54px 16px;
    }

    .kl-contact-section h2 {
      font-size: 32px;
      margin-bottom: 28px;
    }

    .kl-contact-grid {
      grid-template-columns: 1fr;
      gap: 18px;
    }

    .kl-contact-card {
      padding: 28px 24px;
      min-height: auto;
    }
  }