/* roulang page: index */
:root {
      --primary: #0A2647;
      --primary-deep: #14365D;
      --accent: #FF6B35;
      --accent-hover: #E85A2A;
      --highlight: #00C9A7;
      --bg-light: #F8F9FC;
      --bg-section: #EEF1F6;
      --card-bg: #FFFFFF;
      --text-primary: #0A2647;
      --text-body: #3A3F47;
      --text-muted: #7B8088;
      --text-on-dark: #FFFFFF;
      --border-light: #E8ECF2;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 6px;
      --shadow-card: 0px 4px 20px rgba(10, 38, 71, 0.06);
      --shadow-hover: 0px 12px 32px rgba(10, 38, 71, 0.10);
      --transition: 0.25s ease;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --section-gap: 80px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
      width: 100%;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      color: var(--text-primary);
      line-height: 1.3;
    }

    h1 {
      font-size: 48px;
      letter-spacing: -1px;
      margin-bottom: 20px;
    }

    h2 {
      font-size: 36px;
      margin-bottom: 16px;
    }

    h3 {
      font-size: 22px;
      font-weight: 600;
      letter-spacing: 0.5px;
      margin-bottom: 12px;
    }

    p {
      margin-bottom: 16px;
      color: var(--text-body);
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }

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

    button {
      font-family: inherit;
      cursor: pointer;
      border: none;
      background: none;
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 14px 32px;
      font-size: 16px;
      transition: all var(--transition);
      text-align: center;
      line-height: 1.2;
      white-space: nowrap;
      box-shadow: 0 4px 12px rgba(0,0,0,0.08);
    }

    .btn-primary {
      background: var(--accent);
      color: white;
      border: 2px solid var(--accent);
    }

    .btn-primary:hover {
      background: var(--accent-hover);
      border-color: var(--accent-hover);
      transform: translateY(-2px);
      box-shadow: 0 12px 24px rgba(255, 107, 53, 0.3);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
    }

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

    .btn-light {
      background: transparent;
      border: 2px solid rgba(255,255,255,0.7);
      color: white;
    }

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

    .btn-large {
      padding: 18px 48px;
      font-size: 18px;
    }

    @media (max-width: 768px) {
      .btn {
        width: 100%;
        min-height: 48px;
        padding: 12px 24px;
      }
      h1 {
        font-size: 32px;
      }
      h2 {
        font-size: 28px;
      }
      .container {
        padding: 0 20px;
      }
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
      background: transparent;
      backdrop-filter: blur(0px);
      height: 72px;
      display: flex;
      align-items: center;
    }

    .header.scrolled {
      background: rgba(255, 255, 255, 0.95);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }

    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--text-on-dark);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .header.scrolled .logo {
      color: var(--primary);
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      font-weight: 500;
      color: rgba(255,255,255,0.85);
      position: relative;
      padding: 4px 0;
      font-size: 15px;
    }
    .header.scrolled .nav-links a {
      color: var(--text-primary);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 3px;
      background: var(--accent);
      transition: width 0.2s;
      border-radius: 2px;
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 20px;
    }

    .nav-cta {
      margin-left: 16px;
    }
    .header.scrolled .nav-cta .btn-primary {
      background: var(--accent);
      color: white;
    }

    .burger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .burger span {
      width: 28px;
      height: 2px;
      background: white;
      transition: 0.3s;
    }
    .header.scrolled .burger span {
      background: var(--primary);
    }

    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .burger {
        display: flex;
      }
      .mobile-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 32px;
        gap: 28px;
        display: none;
        box-shadow: 0 20px 30px rgba(0,0,0,0.05);
      }
      .mobile-menu.active {
        display: flex;
      }
      .mobile-menu a {
        font-size: 18px;
        font-weight: 600;
        color: var(--primary);
      }
    }

    /* Hero */
    .hero {
      background: linear-gradient(135deg, #0A2647 0%, #14365D 100%);
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 60px;
      color: white;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      color: white;
    }
    .hero-sub {
      font-size: 18px;
      opacity: 0.8;
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-btns {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-visual {
      flex: 1;
      position: relative;
    }
    .hero-img {
      width: 100%;
      border-radius: 24px;
      opacity: 0.9;
      mix-blend-mode: lighten;
    }
    @media (max-width: 768px) {
      .hero-content {
        flex-direction: column;
        text-align: center;
      }
      .hero-text h1 {
        font-size: 36px;
      }
      .hero-btns {
        justify-content: center;
      }
    }

    /* 板块通用 */
    section {
      padding: var(--section-gap) 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .dark-bg {
      background: var(--primary);
      color: white;
    }
    .dark-bg h2, .dark-bg h3 {
      color: white;
    }

    /* 痛点区 */
    .pain-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }
    .pain-cards {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .pain-card {
      background: white;
      padding: 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      border-left: 5px solid var(--accent);
    }
    @media (max-width: 768px) {
      .pain-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 方案卡片 */
    .solutions-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    .solution-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid var(--border-light);
    }
    .solution-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
    }
    @media (max-width: 768px) {
      .solutions-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 数据区 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }
    .stat-number {
      font-size: 56px;
      font-weight: 700;
      color: var(--highlight);
    }
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    /* 证言 */
    .testimonial-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
    }
    .testimonial-card {
      background: white;
      padding: 32px;
      border-radius: var(--radius-card);
      min-width: 340px;
      box-shadow: var(--shadow-card);
    }
    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .faq-item {
      background: #F8F9FC;
      border-radius: var(--radius-card);
      padding: 18px 24px;
      cursor: pointer;
    }
    @media (max-width: 768px) {
      .faq-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 页脚 */
    .footer {
      background: var(--primary);
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }