/* roulang page: index */
:root {
      --primary: #6C3CF0;
      --primary-light: #8B5CF6;
      --accent: #FF5E3A;
      --accent-light: #FF8A6B;
      --dark-bg: #0F0A1A;
      --dark-bg-alt: #1A1035;
      --light-bg: #F8F6FC;
      --card-bg: #FFFFFF;
      --body-text: #2D2640;
      --muted-text: #7B748A;
      --success: #00D68F;
      --gradient-hero: linear-gradient(135deg, #0F0A1A 0%, #1A1035 50%, #2D1B5E 100%);
      --gradient-btn: linear-gradient(135deg, #6C3CF0 0%, #8B5CF6 100%);
      --gradient-accent: linear-gradient(135deg, #FF5E3A 0%, #FF8A6B 100%);
      --gradient-bar: linear-gradient(180deg, #6C3CF0 0%, #FF5E3A 100%);
      --shadow-card: 0 4px 24px rgba(108, 60, 240, 0.08);
      --shadow-card-hover: 0 12px 40px rgba(108, 60, 240, 0.15);
      --shadow-btn: 0 8px 24px rgba(108, 60, 240, 0.3);
      --shadow-btn-hover: 0 12px 32px rgba(108, 60, 240, 0.45);
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-xs: 8px;
      --radius-full: 50px;
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', 'SF Pro Display', 'PingFang SC', sans-serif;
      --transition: 0.3s ease;
      --container-max: 1200px;
      --section-gap: 100px;
      --section-gap-mobile: 60px;
    }

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

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

    body {
      font-family: var(--font-body);
      background-color: var(--light-bg);
      color: var(--body-text);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all var(--transition);
      font-weight: 600;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* Header & Navigation */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(15, 10, 26, 0.88);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(108, 60, 240, 0.18);
      transition: background var(--transition);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 4px;
      color: #FFFFFF;
      font-weight: 800;
      font-size: 1.5rem;
      letter-spacing: -0.3px;
      flex-shrink: 0;
    }

    .logo span {
      background: var(--gradient-btn);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .logo small {
      font-size: 0.7rem;
      font-weight: 400;
      color: rgba(255, 255, 255, 0.55);
      margin-left: 6px;
      letter-spacing: 0.2px;
      -webkit-text-fill-color: rgba(255,255,255,0.6);
      background: none;
    }

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

    .nav-menu a {
      color: rgba(255, 255, 255, 0.7);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 6px 0;
      transition: color var(--transition);
    }

    .nav-menu a:hover,
    .nav-menu a.active {
      color: #FFFFFF;
    }

    .nav-menu a.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--accent);
      border-radius: 1px;
    }

    .header-cta {
      background: var(--gradient-btn);
      color: #fff;
      padding: 10px 24px;
      border-radius: var(--radius-full);
      font-size: 0.9rem;
      box-shadow: 0 4px 15px rgba(108,60,240,0.4);
    }

    .header-cta:hover {
      box-shadow: 0 8px 24px rgba(108,60,240,0.6);
      transform: translateY(-1px);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }

    .hamburger span {
      width: 26px;
      height: 2.5px;
      background: #FFFFFF;
      border-radius: 4px;
      transition: var(--transition);
    }

    .mobile-nav {
      display: none;
    }

    @media (max-width: 768px) {
      .nav-menu, .header-cta.desktop-only {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .mobile-nav {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--dark-bg);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 36px;
        transform: translateX(100%);
        transition: transform 0.4s ease;
        z-index: 999;
        list-style: none;
      }
      .mobile-nav.active {
        transform: translateX(0);
      }
      .mobile-nav a {
        font-size: 1.4rem;
        color: #fff;
        font-weight: 600;
      }
      .mobile-nav .close-btn {
        position: absolute;
        top: 24px;
        right: 28px;
        font-size: 2rem;
        color: #fff;
        background: none;
        border: none;
      }
    }

    /* Hero */
    .hero {
      background: var(--gradient-hero);
      padding: 140px 0 100px;
      position: relative;
      overflow: hidden;
    }

    .hero::before {
      content: "";
      position: absolute;
      width: 400px;
      height: 400px;
      background: radial-gradient(circle, rgba(108,60,240,0.2) 0%, transparent 70%);
      top: -80px;
      right: -100px;
      border-radius: 50%;
    }

    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }

    .hero-text {
      flex: 1;
    }

    .hero-badge {
      display: inline-block;
      background: rgba(108,60,240,0.2);
      color: #D4C5F9;
      padding: 6px 16px;
      border-radius: 20px;
      font-size: 0.85rem;
      margin-bottom: 24px;
    }

    .hero h1 {
      font-size: 3rem;
      font-weight: 800;
      line-height: 1.2;
      color: #FFFFFF;
      margin-bottom: 20px;
      letter-spacing: -0.5px;
    }

    .hero p {
      color: rgba(255,255,255,0.65);
      font-size: 1.1rem;
      margin-bottom: 36px;
      max-width: 480px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--gradient-btn);
      color: #fff;
      padding: 16px 40px;
      border-radius: var(--radius-full);
      box-shadow: var(--shadow-btn);
    }

    .btn-primary:hover {
      box-shadow: var(--shadow-btn-hover);
      transform: scale(1.03);
    }

    .btn-outline {
      border: 2px solid var(--primary);
      color: #FFFFFF;
      padding: 16px 40px;
      border-radius: var(--radius-full);
    }

    .btn-outline:hover {
      background: var(--primary);
      color: #fff;
    }

    .hero-image {
      flex: 1;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 360px;
      border-radius: var(--radius-lg);
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    }

    .hero-stats {
      display: flex;
      gap: 24px;
      margin-top: 30px;
    }

    .stat-badge {
      background: rgba(255,255,255,0.08);
      backdrop-filter: blur(8px);
      padding: 10px 18px;
      border-radius: var(--radius-xs);
      color: #fff;
    }

    .stat-badge strong {
      color: var(--accent);
      font-family: var(--font-number);
      font-size: 1.4rem;
    }

    @media (max-width: 768px) {
      .hero .container {
        flex-direction: column;
      }
      .hero h1 {
        font-size: 2.2rem;
      }
      .hero-image {
        width: 100%;
        min-height: 240px;
      }
    }

    /* Sections */
    section {
      padding: var(--section-gap) 0;
    }

    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--dark-bg);
    }

    .section-sub {
      color: var(--muted-text);
      margin-bottom: 48px;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 32px;
      box-shadow: var(--shadow-card);
      border: 1px solid rgba(108,60,240,0.05);
      transition: all var(--transition);
    }

    .card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-6px);
    }

    .icon-circle {
      width: 56px;
      height: 56px;
      background: #F0EBFF;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.8rem;
      color: var(--primary);
      margin-bottom: 20px;
    }

    .pain-card h3 {
      font-size: 1.3rem;
      margin-bottom: 8px;
    }

    .solution-card {
      position: relative;
      overflow: hidden;
    }

    .solution-card img {
      width: 100%;
      border-radius: 12px;
      height: 180px;
      object-fit: cover;
      margin-bottom: 16px;
    }

    .data-badge {
      position: absolute;
      top: 16px;
      right: 16px;
      background: var(--gradient-accent);
      color: #fff;
      padding: 6px 16px;
      border-radius: 20px;
      font-weight: 700;
      font-family: var(--font-number);
    }

    .results-area {
      background: var(--light-bg);
      border-radius: var(--radius-lg);
      display: flex;
      align-items: center;
      gap: 40px;
      padding: 48px;
    }

    .big-number {
      font-size: 4.5rem;
      font-weight: 800;
      font-family: var(--font-number);
      background: linear-gradient(135deg, var(--primary), var(--accent));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .testimonial-card {
      display: flex;
      border-left: 4px solid;
      border-image: var(--gradient-bar) 1;
      padding-left: 20px;
    }

    .faq-item {
      border-bottom: 1px solid rgba(108,60,240,0.1);
      padding: 18px 0;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      cursor: pointer;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: #F4F0FF;
      margin-top: 10px;
      padding: 0 16px;
      border-radius: 8px;
    }

    .faq-answer.open {
      max-height: 200px;
      padding: 16px;
    }

    .cta-section {
      background: var(--dark-bg);
      text-align: center;
      color: #fff;
    }

    footer {
      background: var(--dark-bg);
      color: rgba(255,255,255,0.5);
      padding: 48px 0 24px;
    }

    @media (max-width: 768px) {
      .grid-3 {
        grid-template-columns: 1fr;
      }
      .results-area {
        flex-direction: column;
      }
    }