/* roulang page: index */
:root {
      --primary: #0A0F1E;
      --accent: #FF4D2E;
      --accent-hover: #E03E1F;
      --bg-white: #FFFFFF;
      --bg-light: #F8F9FA;
      --text-dark: #1F2937;
      --text-soft: #6B7280;
      --border-light: #E5E7EB;
      --shadow-sm: 0 10px 25px -5px rgba(0,0,0,0.03), 0 8px 10px -6px rgba(0,0,0,0.02);
      --radius-none: 0px;
      --font-heading: 'Inter', 'Noto Sans SC', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
      --font-body: 'Noto Serif SC', 'Inter', system-ui, -apple-system, 'Segoe UI', Georgia, serif;
      --font-number: 'DIN Alternate', 'Inter', 'Noto Sans SC', sans-serif;
      --transition: 0.3s ease;
      --spacing-section: 6rem;
    }

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

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

    body {
      font-family: var(--font-body);
      color: var(--text-dark);
      background-color: var(--bg-white);
      line-height: 1.8;
      letter-spacing: 0.5px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 40px;
    }

    h1, h2, h3, .number-stat {
      font-family: var(--font-heading);
      font-weight: 600;
      line-height: 1.25;
    }

    h1 {
      font-size: 48px;
      line-height: 60px;
      letter-spacing: -0.5px;
    }

    h2 {
      font-size: 36px;
      line-height: 48px;
      margin-bottom: 1.5rem;
    }

    .section-title {
      margin-bottom: 1rem;
      position: relative;
    }

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

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

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

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 0.85rem 2.2rem;
      font-family: var(--font-heading);
      font-weight: 600;
      font-size: 16px;
      border: 1px solid transparent;
      cursor: pointer;
      transition: all var(--transition);
      text-align: center;
      border-radius: 0px;
      letter-spacing: 0.7px;
    }

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

    .btn-primary:hover {
      background-color: var(--accent-hover);
      border-color: var(--accent-hover);
      transform: scale(1.02);
    }

    .btn-outline {
      background: transparent;
      color: var(--accent);
      border-color: var(--accent);
    }

    .btn-outline:hover {
      background-color: var(--accent);
      color: white;
      transform: scale(1.02);
    }

    .btn-white {
      background: white;
      color: var(--accent);
      border-color: white;
    }

    .btn-white:hover {
      background: #f3f4f6;
      transform: scale(1.02);
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: rgba(255,255,255,0.8);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid rgba(229,231,235,0.4);
      transition: background var(--transition);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.6rem;
      letter-spacing: 1px;
      color: var(--primary);
    }

    .logo-icon {
      display: flex;
      align-items: center;
      justify-content: center;
      width: 28px;
      height: 28px;
      background: var(--accent);
      color: white;
      font-weight: bold;
      margin-right: 4px;
      position: relative;
      transform: rotate(0deg);
    }

    .nav-links {
      display: flex;
      gap: 2.2rem;
      align-items: center;
      font-family: var(--font-heading);
      font-weight: 500;
      color: var(--text-dark);
    }

    .nav-links a {
      padding: 0.25rem 0;
      border-bottom: 2px solid transparent;
      transition: 0.2s;
      font-size: 1rem;
    }

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

    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 1.6rem;
      color: var(--primary);
      cursor: pointer;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #f8f9fa 0%, #ffffff 100%);
      padding-top: 80px;
      overflow: hidden;
      position: relative;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
      width: 100%;
    }

    .hero-content h1 {
      background: linear-gradient(135deg, var(--accent) 0%, var(--primary) 80%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.5rem;
    }

    .hero-content p {
      font-size: 1.25rem;
      color: var(--text-soft);
      margin-bottom: 2rem;
      max-width: 90%;
    }

    .hero-visual {
      position: relative;
      height: 450px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 0px;
      opacity: 0.95;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    .overlay-graphic {
      width: 100%;
      height: 100%;
      background: rgba(10, 15, 30, 0.1);
      backdrop-filter: blur(2px);
    }

    /* 痛点区 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 1.5rem;
      margin-top: 3rem;
    }

    .pain-card {
      background: white;
      border: 1px solid var(--border-light);
      padding: 2rem 1.8rem;
      transition: all var(--transition);
    }

    .pain-card:hover {
      border-color: var(--accent);
      transform: translateY(-4px);
    }

    .pain-icon {
      font-size: 2rem;
      color: var(--accent);
      margin-bottom: 1rem;
    }

    /* 解决方案图文交替 */
    .solution-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 4rem;
      align-items: center;
      margin-bottom: 5rem;
    }

    .solution-img {
      height: 360px;
      background-size: cover;
      background-position: center;
      background-color: #e5e7eb;
        }

    .solution-list {
      list-style: none;
      margin-top: 1.5rem;
    }

    .solution-list li {
      display: flex;
      align-items: flex-start;
      gap: 10px;
      margin-bottom: 1rem;
    }

    .solution-list li::before {
      content: "■";
      color: var(--accent);
      font-size: 0.9rem;
      line-height: 1.6;
    }

     /* 数据区 */
    .stats-row {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      text-align: center;
      gap: 3rem;
    }

    .stat-number {
      font-family: var(--font-number);
      font-size: 4rem;
      font-weight: 700;
      color: var(--primary);
      line-height: 1.2;
    }

    /* 证言滚动 */
    .testimonials-scroll {
      display: flex;
      gap: 2rem;
      overflow-x: auto;
      padding: 1.5rem 0.2rem;
      scrollbar-width: thin;
    }

    .testimonial-card {
      flex: 0 0 380px;
      background: #f9fafb;
      padding: 2rem;
      border-left: 4px solid var(--accent);
      font-style: italic;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 1.2rem 0;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
      font-family: var(--font-heading);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      color: var(--text-soft);
      background: rgba(10,15,30,0.02);
      padding: 0 1rem;
      margin-top: 0.5rem;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 1rem;
    }

    /* CTA */
    .cta-section {
      background: radial-gradient(circle at 30% 30%, #1a1f33, var(--primary));
      color: white;
    }

    /* Footer */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2.5rem;
    }

    .footer-bottom {
      border-top: 1px solid #374151;
      margin-top: 3rem;
      padding-top: 1.5rem;
      display: flex;
      justify-content: space-between;
      color: #9ca3af;
      font-size: 0.9rem;
    }

    /* 动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(24px);
      transition: opacity 0.7s ease, transform 0.7s ease;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }

    @media (max-width: 1024px) {
      .container { padding: 0 24px; }
      h1 { font-size: 40px; line-height: 52px; }
    }

    @media (max-width: 768px) {
      h1 { font-size: 36px; line-height: 44px; }
      h2 { font-size: 28px; line-height: 38px; }
      .nav-links { display: none; }
      .mobile-menu-btn { display: block; }
      .hero-grid { grid-template-columns: 1fr; }
      .hero-visual { height: 300px; }
      .pain-grid { grid-template-columns: 1fr; }
      .solution-row { grid-template-columns: 1fr; gap: 2rem; }
      .stats-row { grid-template-columns: 1fr; gap: 2rem; }
      .testimonials-scroll { flex-direction: column; }
      .testimonial-card { flex: auto; }
      .footer-grid { grid-template-columns: 1fr; }
    }