/* roulang page: index */
:root {
      --primary-deep-blue: #1A3C6D;
      --accent-racing-red: #E63946;
      --bg-light-gray: #F8FAFC;
      --card-white: #FFFFFF;
      --text-deep: #1E293B;
      --text-muted: #64748B;
      --success-green: #10B981;
      --warning-amber: #F59E0B;
      --border-light: #E2E8F0;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.06), 0 4px 12px rgba(0,0,0,0.04);
      --shadow-card-hover: 0 2px 8px rgba(26,60,109,0.12), 0 8px 24px rgba(0,0,0,0.06);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
      --font-number: "Inter", "SF Pro Display", system-ui, sans-serif;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light-gray);
      color: var(--text-deep);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 1.25rem;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--card-white);
      border-bottom: 1px solid var(--border-light);
      z-index: 1000;
      height: 64px;
      display: flex;
      align-items: center;
      transition: box-shadow 0.2s;
    }

    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 1.25rem;
    }

    .logo {
      font-size: 1.35rem;
      font-weight: 700;
      color: var(--primary-deep-blue);
      text-decoration: none;
      display: flex;
      align-items: center;
      gap: 0.5rem;
      letter-spacing: -0.3px;
    }
    .logo i {
      font-size: 1.8rem;
      color: var(--accent-racing-red);
    }

    .nav-menu {
      display: flex;
      gap: 2rem;
      align-items: center;
      list-style: none;
    }

    .nav-menu a {
      text-decoration: none;
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-deep);
      position: relative;
      padding: 0.25rem 0;
      transition: color 0.2s;
    }

    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-racing-red);
      transition: width 0.25s ease;
    }

    .nav-menu a:hover {
      color: var(--accent-racing-red);
    }
    .nav-menu a:hover::after {
      width: 100%;
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary-deep-blue);
      cursor: pointer;
      padding: 0.5rem;
    }

    @media (max-width: 1023px) {
      .hamburger {
        display: block;
      }
      .nav-menu {
        position: fixed;
        top: 64px;
        left: 0;
        width: 100%;
        background: var(--card-white);
        flex-direction: column;
        align-items: flex-start;
        padding: 1.5rem 2rem;
        gap: 1.25rem;
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        transform: translateY(-120%);
        opacity: 0;
        transition: transform 0.3s ease, opacity 0.2s;
        border-bottom: 1px solid var(--border-light);
        z-index: 999;
      }
      .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
      }
      .nav-menu a {
        font-size: 1.1rem;
        width: 100%;
        padding: 0.5rem 0;
        border-bottom: 1px solid #f1f5f9;
      }
    }

    /* 区块通用 */
    section {
      padding: 5rem 0;
    }
    @media (max-width: 767px) {
      section {
        padding: 3.5rem 0;
      }
    }

    .section-title {
      font-size: 2rem;
      font-weight: 700;
      color: var(--primary-deep-blue);
      text-align: center;
      margin-bottom: 0.75rem;
    }
    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 3rem;
    }

    /* Hero */
    #hero {
      padding-top: 8rem;
      padding-bottom: 5rem;
      background: radial-gradient(circle at 20% 30%, rgba(26,60,109,0.04) 0%, transparent 60%);
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
    }
    .hero-right img {
      width: 100%;
      border-radius: 16px;
      box-shadow: var(--shadow-card-hover);
      aspect-ratio: 4/3;
      object-fit: cover;
    }
    h1 {
      font-size: 2.75rem;
      font-weight: 800;
      color: var(--primary-deep-blue);
      line-height: 1.25;
      letter-spacing: -0.02em;
      margin-bottom: 1.25rem;
    }
    .hero-desc {
      font-size: 1.125rem;
      color: var(--text-muted);
      margin-bottom: 2rem;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-racing-red);
      color: white;
      font-weight: 700;
      padding: 0.85rem 2.2rem;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: all 0.2s ease;
      border: none;
      cursor: pointer;
      font-size: 1.125rem;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      background: #C1121F;
      transform: scale(1.02);
    }
    .btn-secondary {
      background: transparent;
      border: 1.5px solid var(--primary-deep-blue);
      color: var(--primary-deep-blue);
      font-weight: 600;
      padding: 0.85rem 2.2rem;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: 0.2s;
    }
    .btn-secondary:hover {
      background: #EBF2FA;
    }

    @media (max-width: 767px) {
      .hero-grid {
        flex-direction: column;
      }
      h1 {
        font-size: 2rem;
      }
      .btn-group .btn-primary, .btn-group .btn-secondary {
        width: 100%;
        text-align: center;
      }
    }

    /* 解决方案卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.5rem;
    }
    .solution-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      transition: all 0.25s;
      display: flex;
      flex-direction: column;
    }
    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-card-hover);
    }
    .card-icon {
      width: 56px;
      height: 56px;
      background: #EBF2FA;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 1.25rem;
      font-size: 1.8rem;
      color: var(--primary-deep-blue);
    }
    .pain-point {
      font-size: 0.8rem;
      font-weight: 600;
      color: var(--warning-amber);
      margin-bottom: 0.5rem;
    }
    .pain-desc {
      font-size: 0.9rem;
      color: var(--text-muted);
      margin-bottom: 1rem;
    }
    .divider {
      border-top: 1px dashed var(--border-light);
      margin: 1rem 0;
    }
    .card-title {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--text-deep);
      margin-bottom: 0.5rem;
    }

    @media (max-width: 1023px) {
      .cards-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .cards-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 成果 */
    #results {
      background: #F1F5F9;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
      text-align: center;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      font-family: var(--font-number);
      font-feature-settings: "tnum";
      color: var(--accent-racing-red);
    }
    .stat-label {
      color: var(--text-muted);
      font-size: 1rem;
    }
    @media (max-width: 640px) {
      .stats-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 2rem;
    }
    .testimonial-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 2rem;
      box-shadow: var(--shadow-card);
      position: relative;
    }
    .testimonial-card::before {
      content: "“";
      font-size: 4rem;
      color: var(--accent-racing-red);
      opacity: 0.15;
      position: absolute;
      top: 0;
      left: 1.5rem;
      line-height: 1;
    }
    .quote {
      font-style: italic;
      font-size: 1.1rem;
      margin-bottom: 1.5rem;
    }
    .user-info {
      display: flex;
      align-items: center;
      gap: 0.75rem;
    }
    .avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #CBD5E1;
    }
    @media (max-width: 640px) {
      .testimonial-grid {
        grid-template-columns: 1fr;
      }
    }

    /* FAQ */
    .faq-container {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 0.5rem;
    }
    .faq-question {
      font-weight: 600;
      color: var(--primary-deep-blue);
      padding: 1rem 0;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease;
      background: #F8FAFC;
      padding: 0 1rem;
      color: var(--text-muted);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 1rem;
    }
    .faq-item.active .faq-question i {
      transform: rotate(180deg);
    }

    /* CTA */
    .cta-band {
      background: var(--primary-deep-blue);
      padding: 5rem 1.25rem;
      text-align: center;
      color: white;
    }
    .cta-band h2 {
      color: white;
      font-size: 2.5rem;
      margin-bottom: 1rem;
    }
    .cta-sub {
      color: #CBD5E1;
      margin-bottom: 2rem;
    }

    footer {
      background: #1E293B;
      color: #94A3B8;
      padding: 2rem 1.25rem;
    }
    .footer-inner {
      display: flex;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 1rem;
    }