/* roulang page: index */
:root {
      --primary: #E63946;
      --primary-dark: #C1121F;
      --secondary: #1D3557;
      --accent: #F4A261;
      --success: #2A9D8F;
      --bg-light: #F8F9FA;
      --white: #FFFFFF;
      --text-dark: #1E1E1E;
      --text-muted: #6C757D;
      --border-light: #E9ECEF;
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 30px rgba(230,57,70,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-title: 'Noto Sans SC', 'PingFang SC', sans-serif;
      --font-body: 'Noto Sans SC', 'PingFang SC', sans-serif;
      --font-number: 'Roboto', 'Noto Sans SC', sans-serif;
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--bg-light);
      color: var(--text-dark);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-title);
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 1rem;
    }

    h1 {
      font-size: 48px;
      line-height: 1.2;
    }

    h2 {
      font-size: 36px;
      line-height: 1.3;
    }

    h3 {
      font-size: 24px;
      line-height: 1.4;
      font-weight: 600;
    }

    p {
      margin-bottom: 1.5rem;
      color: var(--text-dark);
    }

    .text-muted {
      color: var(--text-muted);
    }

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

    a {
      color: var(--primary);
      text-decoration: none;
      transition: color 0.2s;
    }

    a:hover {
      color: var(--primary-dark);
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 按钮系统 */
    .btn-primary {
      background: var(--primary);
      color: white;
      border: none;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      display: inline-block;
      text-align: center;
      transition: all 0.25s ease;
      box-shadow: 0 4px 12px rgba(230,57,70,0.25);
      cursor: pointer;
      border: 2px solid transparent;
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(193,18,31,0.35);
      color: white;
    }

    .btn-outline {
      background: transparent;
      color: var(--primary);
      border: 2px solid var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      display: inline-block;
      transition: all 0.25s ease;
      cursor: pointer;
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
      transform: translateY(-2px);
    }

    .btn-lg {
      padding: 18px 40px;
      font-size: 18px;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: transparent;
      transition: all 0.3s ease;
      padding: 15px 0;
    }

    #header.scrolled {
      background: var(--white);
      box-shadow: 0 2px 12px rgba(0,0,0,0.06);
      padding: 10px 0;
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    .logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 28px;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .logo i {
      font-size: 26px;
      color: var(--accent);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-links a {
      color: var(--secondary);
      font-weight: 500;
      font-size: 16px;
      padding-bottom: 6px;
      border-bottom: 3px solid transparent;
      transition: all 0.2s;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }

    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 10px 24px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border-bottom: none !important;
    }

    .nav-cta:hover {
      background: var(--primary-dark);
    }

    .mobile-toggle {
      display: none;
      font-size: 28px;
      color: var(--secondary);
      cursor: pointer;
    }

    /* Hero */
    #hero {
      min-height: 100vh;
      background: var(--secondary);
      position: relative;
      display: flex;
      align-items: center;
      overflow: hidden;
    }

    .hero-bg-shape {
      position: absolute;
      right: 0;
      bottom: 0;
      width: 45%;
      height: 100%;
      background: var(--primary);
      clip-path: polygon(25% 0%, 100% 0%, 100% 100%, 0% 100%);
      opacity: 0.9;
    }

    .hero-content {
      display: flex;
      align-items: center;
      justify-content: space-between;
      position: relative;
      z-index: 2;
      width: 100%;
    }

    .hero-text {
      flex: 1;
      padding-right: 40px;
    }

    .hero-text h1 {
      color: white;
      margin-bottom: 1.5rem;
    }

    .hero-text .subtitle {
      font-size: 18px;
      color: #F1F2F6;
      margin-bottom: 2rem;
      line-height: 1.6;
    }

    .hero-image {
      flex: 1;
      position: relative;
    }

    .hero-image img {
      border-radius: 4px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.3);
      width: 100%;
      object-fit: cover;
      aspect-ratio: 4/3;
    }

    /* 通用区块 */
    section {
      padding: 80px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }

    .section-title h2 {
      margin-bottom: 0.5rem;
    }

    .divider {
      width: 60px;
      height: 4px;
      background: var(--primary);
      margin: 12px auto 0;
    }

    /* 痛点卡片 */
    .problem-grid {
      display: flex;
      gap: 30px;
      flex-wrap: wrap;
    }

    .problem-card {
      background: var(--white);
      padding: 28px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      flex: 1 1 280px;
      border-left: 4px solid var(--primary);
      transition: all 0.3s;
    }

    .problem-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }

    .problem-card i {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 16px;
    }

    /* 解决方案 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 60px;
      flex-wrap: wrap;
    }

    .solution-row.reverse {
      flex-direction: row-reverse;
    }

    .solution-img {
      flex: 1 1 400px;
    }

    .solution-img img {
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      width: 100%;
    }

    .solution-text {
      flex: 1 1 400px;
    }

    .solution-text ul {
      list-style: none;
    }

    .solution-text li {
      margin-bottom: 12px;
      display: flex;
      align-items: flex-start;
      gap: 12px;
    }

    .solution-text li::before {
      content: "●";
      color: var(--primary);
      font-weight: bold;
      font-size: 20px;
      line-height: 1;
    }

    /* 数据卡片 */
    .results-grid {
      display: flex;
      gap: 24px;
      flex-wrap: wrap;
      justify-content: center;
    }

    .stat-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      text-align: center;
      flex: 1 1 200px;
      transition: 0.3s;
    }

    .stat-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }

    .stat-number {
      font-family: var(--font-number);
      font-weight: 700;
      font-size: 44px;
      color: var(--accent);
      line-height: 1.2;
    }

    .stat-label {
      color: var(--text-muted);
      margin-top: 8px;
    }

    /* 证言 */
    .testimonial-grid {
      display: flex;
      gap: 30px;
      flex-wrap: wrap;
    }

    .testimonial-card {
      background: var(--white);
      padding: 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      flex: 1 1 300px;
      display: flex;
      gap: 20px;
      align-items: flex-start;
      transition: 0.3s;
    }

    .testimonial-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    .avatar {
      width: 64px;
      height: 64px;
      border-radius: 50%;
      background: #ddd;
      flex-shrink: 0;
      background-size: cover;
    }

    .quote {
      font-style: italic;
      font-size: 15px;
      color: var(--text-dark);
      position: relative;
      padding-left: 16px;
      border-left: 3px solid var(--primary);
    }

    /* CTA */
    .cta-section {
      background: var(--secondary);
      text-align: center;
      padding: 80px 20px;
    }

    .cta-section h2 {
      color: white;
    }

    .cta-section p {
      color: #F1F2F6;
      margin-bottom: 2rem;
    }

    /* FAQ */
    .accordion-item {
      margin-bottom: 12px;
      border-radius: 8px;
      overflow: hidden;
    }

    .accordion-title {
      background: var(--white);
      padding: 18px 24px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-left: 4px solid var(--primary);
      transition: 0.2s;
    }

    .accordion-title:hover {
      background: #f1f1f1;
    }

    .accordion-content {
      background: var(--bg-light);
      padding: 0 24px 18px;
      display: none;
    }

    .accordion-item.active .accordion-content {
      display: block;
    }

    /* Footer */
    #footer {
      background: var(--secondary);
      color: #F1F2F6;
      padding: 60px 0 20px;
    }

    .footer-grid {
      display: flex;
      gap: 40px;
      flex-wrap: wrap;
      justify-content: space-between;
    }

    .footer-col {
      flex: 1 1 200px;
    }

    .footer-col h4 {
      color: white;
      margin-bottom: 16px;
    }

    .footer-col a {
      color: #ccc;
      display: block;
      margin-bottom: 8px;
    }

    .copyright {
      text-align: center;
      margin-top: 40px;
      color: var(--text-muted);
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
    }

    @media (max-width: 1024px) {
      h1 { font-size: 40px; }
      .hero-content { flex-direction: column; }
      .hero-text { padding-right: 0; margin-bottom: 30px; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; flex-direction: column; background: white; position: absolute; top: 70px; left: 20px; right: 20px; padding: 20px; border-radius: 12px; box-shadow: 0 10px 25px rgba(0,0,0,0.1); }
      .nav-links.open { display: flex; }
      .mobile-toggle { display: block; }
      section { padding: 60px 0; }
      .solution-row, .solution-row.reverse { flex-direction: column; }
    }

    @media (max-width: 520px) {
      h1 { font-size: 32px; }
      h2 { font-size: 28px; }
    }