/* roulang page: index */
:root {
      --primary: #7B2FFF;
      --primary-glow: #5D3FD3;
      --secondary: #FF5E1A;
      --secondary-bright: #FF7B3D;
      --bg-deep: #0B0C10;
      --bg-elevated: #1A1C26;
      --bg-card: #1E2130;
      --text-primary: #FFFFFF;
      --text-secondary: #B0B8C5;
      --text-muted: #8A92A3;
      --border-dim: rgba(255,255,255,0.06);
      --border-glow: rgba(123,47,255,0.5);
      --radius-md: 12px;
      --radius-lg: 16px;
      --radius-btn: 8px;
      --shadow-card: 0 8px 32px rgba(0,0,0,0.4);
      --shadow-glow: 0 0 20px rgba(123,47,255,0.5);
      --font-sans: 'Inter', 'PingFang SC', 'Noto Sans SC', '阿里巴巴普惠体', '思源黑体', system-ui, sans-serif;
      --font-display: 'Rajdhani', 'Inter', 'PingFang SC', sans-serif;
      --transition: all 0.25s ease;
    }

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

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-deep);
    }

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

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      backdrop-filter: blur(12px);
      background: rgba(11, 12, 16, 0.85);
      border-bottom: 1px solid var(--border-dim);
      transition: var(--transition);
      padding: 0 24px;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      height: 70px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.6rem;
      letter-spacing: 2px;
      color: white;
      text-decoration: none;
      font-family: var(--font-display);
    }
    .logo i {
      color: var(--secondary);
      font-size: 2rem;
      text-shadow: 0 0 12px var(--secondary);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 28px;
      list-style: none;
    }
    .nav-menu a {
      text-decoration: none;
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      letter-spacing: 0.5px;
      position: relative;
      padding: 6px 0;
      transition: color 0.2s;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--secondary);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--secondary);
      transition: width 0.25s ease;
      box-shadow: 0 0 10px var(--secondary);
    }
    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: white;
      background: none;
      border: none;
      cursor: pointer;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      position: relative;
      background: radial-gradient(circle at 30% 40%, rgba(123,47,255,0.25) 0%, transparent 45%),
                  radial-gradient(circle at 70% 60%, rgba(255,94,26,0.18) 0%, transparent 50%),
                  var(--bg-deep);
      overflow: hidden;
    }
    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.25;
      mix-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 900px;
      padding: 0 20px;
    }
    .hero h1 {
      font-size: clamp(2.8rem, 7vw, 4.2rem);
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 1.5rem;
      letter-spacing: 2px;
      text-shadow: 0 0 30px rgba(123,47,255,0.5);
    }
    .hero .subtitle {
      font-size: 1.25rem;
      color: var(--text-secondary);
      margin-bottom: 2.5rem;
      max-width: 700px;
      margin-left: auto;
      margin-right: auto;
    }
    .btn-group {
      display: flex;
      flex-wrap: wrap;
      gap: 20px;
      justify-content: center;
    }
    .btn-primary {
      background: var(--secondary);
      color: white;
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      box-shadow: 0 0 18px rgba(255,94,26,0.6);
      transition: var(--transition);
      border: none;
      cursor: pointer;
      font-size: 1rem;
    }
    .btn-primary:hover {
      background: var(--secondary-bright);
      box-shadow: 0 0 28px rgba(255,94,26,0.9);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: white;
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }
    .btn-outline:hover {
      background: rgba(123,47,255,0.15);
      border-color: var(--secondary);
      box-shadow: 0 0 15px rgba(123,47,255,0.5);
    }
    .scroll-indicator {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      color: var(--text-muted);
      font-size: 1.8rem;
      animation: bounce 2s infinite;
    }

    @keyframes bounce {
      0%, 100% { transform: translateX(-50%) translateY(0); }
      50% { transform: translateX(-50%) translateY(12px); }
    }

    /* 通用 section */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      text-align: center;
      margin-bottom: 1rem;
      letter-spacing: 1px;
    }
    .section-sub {
      text-align: center;
      color: var(--text-secondary);
      max-width: 700px;
      margin: 0 auto 50px;
      font-size: 1.1rem;
    }

    /* 痛点卡片 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .pain-card {
      background: var(--bg-card);
      border-left: 5px solid var(--secondary);
      border-radius: var(--radius-lg);
      padding: 28px 24px;
      transition: var(--transition);
      border: 1px solid var(--border-dim);
    }
    .pain-card:hover {
      border-color: var(--primary);
      box-shadow: var(--shadow-card);
    }
    .pain-icon {
      font-size: 2.4rem;
      color: var(--primary);
      margin-bottom: 18px;
    }
    .pain-card h4 {
      font-size: 1.4rem;
      margin-bottom: 12px;
    }

    /* 解决方案卡片 不同高度感 */
    .solution-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .solution-card {
      background: var(--bg-elevated);
      border-radius: var(--radius-lg);
      padding: 36px 24px 28px;
      border: 1px solid var(--border-dim);
      transition: all 0.3s;
      display: flex;
      flex-direction: column;
      position: relative;
      overflow: hidden;
    }
    .solution-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 4px;
      background: linear-gradient(90deg, var(--primary), var(--secondary));
    }
    .solution-card:hover {
      border-color: var(--primary);
      box-shadow: 0 16px 40px rgba(123,47,255,0.2);
      transform: translateY(-6px);
    }
    .solution-icon {
      font-size: 2.8rem;
      color: var(--primary);
      text-align: center;
      margin-bottom: 20px;
    }
    .solution-card h3 {
      text-align: center;
      font-size: 1.5rem;
      margin-bottom: 14px;
    }
    .solution-card p {
      color: var(--text-secondary);
      flex: 1;
    }
    .solution-link {
      margin-top: 20px;
      color: var(--secondary);
      font-weight: 600;
      text-decoration: none;
      display: inline-block;
    }

    /* 数据卡片 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-item {
      background: var(--bg-card);
      border-radius: var(--radius-lg);
      padding: 32px 16px;
      text-align: center;
      border: 1px solid var(--border-dim);
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--secondary);
      font-family: var(--font-display);
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      align-items: start;
    }
    .testimonial-card {
      background: var(--bg-elevated);
      border-radius: var(--radius-lg);
      padding: 28px;
      border: 1px solid var(--border-dim);
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .testimonial-card.featured {
      transform: scale(1.02);
      border-color: var(--primary);
    }
    .testimonial-header {
      display: flex;
      align-items: center;
      gap: 14px;
    }
    .avatar {
      width: 56px;
      height: 56px;
      border-radius: 50%;
      background: var(--primary);
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: bold;
      border: 2px solid var(--secondary);
      box-shadow: 0 0 15px var(--secondary);
      color: white;
      font-size: 1.4rem;
    }
    .user-info strong {
      display: block;
    }
    .badge {
      background: var(--primary);
      color: white;
      padding: 2px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
      display: inline-block;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--bg-elevated);
      border: 1px solid var(--border-dim);
      border-radius: var(--radius-md);
      margin-bottom: 16px;
      overflow: hidden;
    }
    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      color: white;
      padding: 20px 24px;
      font-size: 1.1rem;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      text-align: left;
    }
    .faq-answer {
      padding: 0 24px 20px;
      color: var(--text-secondary);
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active {
      border-color: var(--primary);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #2d1b4e 0%, #1a1030 100%);
      text-align: center;
      padding: 80px 24px;
      border-radius: 32px;
      margin: 60px 0;
    }
    .cta-section h2 {
      font-size: 2.8rem;
      margin-bottom: 1rem;
    }

    /* Footer */
    .footer {
      background: #0A0B0F;
      padding: 60px 0 20px;
      border-top: 1px solid var(--border-dim);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    .back-to-top {
      position: fixed;
      bottom: 24px;
      right: 24px;
      background: var(--primary);
      color: white;
      width: 48px;
      height: 48px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      box-shadow: 0 0 18px var(--primary);
    }

    @media (max-width: 1024px) {
      .pain-grid, .solution-grid, .testimonial-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; flex-direction: column; position: absolute; top: 70px; left: 0; width: 100%; background: rgba(11,12,16,0.95); padding: 20px; }
      .nav-menu.active { display: flex; }
      .hamburger { display: block; }
      .pain-grid, .solution-grid, .testimonial-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 520px) {
      .stats-grid { grid-template-columns: 1fr; }
      .btn-group { flex-direction: column; align-items: center; }
    }