/* roulang page: index */
:root {
      --primary-black: #1A1A1A;
      --accent-orange: #E85D04;
      --warm-gold: #F4A261;
      --deep-green: #2A9D8F;
      --bg-light: #F9F9FB;
      --card-white: #FFFFFF;
      --dark-bg: #1E1E1E;
      --text-muted: #6B6B7B;
      --border-light: #E5E5EB;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --radius-container: 16px;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --font-sans: "Inter", "PingFang SC", "Noto Sans SC", "Helvetica Neue", sans-serif;
      --section-gap: 100px;
      --container-max: 1200px;
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--primary-black);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      padding-top: 70px;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      letter-spacing: -0.02em;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: color 0.2s ease;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(249, 249, 251, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid transparent;
      transition: background 0.3s, border-color 0.3s, box-shadow 0.3s;
      padding: 0 24px;
    }

    .main-nav.scrolled {
      background: rgba(26, 26, 26, 0.96);
      border-bottom: 1px solid rgba(255,255,255,0.1);
      box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    }

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

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--primary-black);
      transition: color 0.2s;
    }
    .main-nav.scrolled .logo {
      color: white;
    }
    .logo .accent {
      color: var(--accent-orange);
    }
    .main-nav.scrolled .logo .accent {
      color: var(--warm-gold);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-links a {
      font-weight: 500;
      font-size: 1rem;
      color: var(--primary-black);
      padding: 0.25rem 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }
    .main-nav.scrolled .nav-links a {
      color: #ddd;
    }
    .nav-links a:hover {
      color: var(--accent-orange);
      border-bottom-color: var(--accent-orange);
    }
    .main-nav.scrolled .nav-links a:hover {
      color: var(--warm-gold);
      border-bottom-color: var(--warm-gold);
    }

    .btn-nav {
      background: var(--accent-orange);
      color: white !important;
      padding: 0.5rem 1.5rem;
      border-radius: 30px;
      font-weight: 600;
      border: none;
      transition: background 0.2s, transform 0.1s;
    }
    .btn-nav:hover {
      background: #c94d00;
      transform: translateY(-1px);
      border-bottom: none !important;
    }

    .mega-trigger {
      position: relative;
    }
    .mega-panel {
      position: absolute;
      top: 100%;
      left: 0;
      background: var(--card-white);
      border-radius: 16px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.12);
      width: 320px;
      padding: 1.2rem;
      display: none;
      gap: 1.2rem;
      flex-direction: column;
      z-index: 100;
      border: 1px solid var(--border-light);
    }
    .mega-trigger:hover .mega-panel {
      display: flex;
    }
    .mega-item {
      display: flex;
      align-items: flex-start;
      gap: 0.8rem;
      padding: 0.6rem;
      border-radius: 10px;
      transition: background 0.15s;
    }
    .mega-item:hover {
      background: #f5f5f8;
    }
    .mega-item i {
      color: var(--accent-orange);
      font-size: 1.4rem;
      width: 24px;
      text-align: center;
    }
    .mega-item span {
      font-weight: 600;
      display: block;
      font-size: 0.95rem;
    }
    .mega-item small {
      color: var(--text-muted);
      font-size: 0.8rem;
    }

    .hamburger {
      display: none;
      font-size: 1.8rem;
      cursor: pointer;
      color: var(--primary-black);
    }
    .main-nav.scrolled .hamburger {
      color: white;
    }

    /* Hero */
    #hero {
      padding: 3rem 0 4rem;
      background: var(--bg-light);
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
      display: flex;
      justify-content: center;
      align-items: center;
      background: radial-gradient(circle at 30% 30%, rgba(232,93,4,0.08), transparent 70%);
      border-radius: 32px;
      padding: 2rem;
    }
    .hero-badge {
      color: var(--accent-orange);
      font-weight: 600;
      font-size: 0.9rem;
      letter-spacing: 1px;
      margin-bottom: 1rem;
    }
    .hero-title {
      font-size: 3.2rem;
      line-height: 1.2;
      margin-bottom: 1.2rem;
    }
    .hero-desc {
      font-size: 1.2rem;
      color: #4a4a5e;
      margin-bottom: 2rem;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      padding: 0.8rem 2rem;
      border-radius: 30px;
      font-weight: 600;
      display: inline-block;
      transition: 0.2s;
      border: none;
    }
    .btn-primary:hover {
      background: #c94d00;
      color: white;
    }
    .btn-outline {
      border: 2px solid var(--accent-orange);
      color: var(--accent-orange);
      background: transparent;
      padding: 0.8rem 2rem;
      border-radius: 30px;
      font-weight: 600;
      transition: 0.2s;
    }
    .btn-outline:hover {
      background: rgba(232,93,4,0.05);
    }
    .trust-icons {
      display: flex;
      gap: 1.8rem;
      margin-top: 2rem;
      color: #555;
      font-size: 0.9rem;
    }

    /* 区块通用 */
    section {
      padding: var(--section-gap) 0;
    }

    .section-title {
      font-size: 2.2rem;
      margin-bottom: 1rem;
    }
    .section-subtitle {
      color: var(--text-muted);
      max-width: 600px;
      margin-bottom: 3rem;
    }

    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--card-white);
      padding: 2rem 1.5rem;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(232,93,4,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-orange);
      font-size: 1.5rem;
      margin-bottom: 1.5rem;
      transition: 0.2s;
    }
    .service-card:hover .icon-circle {
      background: var(--accent-orange);
      color: white;
    }

    /* 优势数据带 */
    #advantages {
      background: var(--dark-bg);
      color: white;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      font-family: 'Inter', sans-serif;
      background: linear-gradient(135deg, #E85D04, #F4A261);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    /* 案例横向滚动 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 1rem;
      scroll-snap-type: x mandatory;
    }
    .case-card {
      min-width: 340px;
      background: var(--card-white);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      overflow: hidden;
      scroll-snap-align: start;
      transition: 0.2s;
    }
    .case-card:hover {
      transform: translateY(-4px);
    }
    .case-img {
      position: relative;
    }
    .case-img img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .tag {
      position: absolute;
      top: 12px;
      left: 12px;
      background: var(--accent-orange);
      color: white;
      padding: 0.2rem 0.8rem;
      border-radius: 20px;
      font-size: 0.75rem;
      font-weight: 600;
    }

    /* 解决方案交替 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 3rem;
      margin-bottom: 4rem;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-text, .solution-img {
      flex: 1;
    }
    .solution-img img {
      border-radius: var(--radius-container);
      box-shadow: var(--shadow-card);
    }

    /* FAQ */
    .accordion-title {
      font-size: 1.1rem;
      font-weight: 600;
      border-left: 3px solid transparent;
      padding-left: 1rem;
      transition: 0.2s;
    }
    .accordion-item.is-active .accordion-title {
      border-left-color: var(--accent-orange);
      background: #f5f5f8;
    }

    /* 联系 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
    }
    input, textarea {
      border-radius: var(--radius-input);
      border: 1px solid #ddd;
      padding: 0.8rem;
      width: 100%;
    }
    input:focus, textarea:focus {
      border-color: var(--accent-orange);
      outline: none;
    }

    /* 页脚 */
    footer {
      background: #1A1A1A;
      color: #AAAAAA;
      padding: 4rem 0 2rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2rem;
    }

    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .hero-grid { flex-direction: column; }
      .hero-title { font-size: 2.2rem; }
      .services-grid, .stats-grid { grid-template-columns: 1fr; }
      .solution-row, .solution-row.reverse { flex-direction: column; }
      .contact-grid, .footer-grid { grid-template-columns: 1fr; }
      .case-card { min-width: 85vw; }
    }