/* roulang page: index */
:root {
      --primary: #7B2FF7;
      --primary-dark: #6918E0;
      --accent: #00F0B5;
      --bg: #FAFAFC;
      --deep-bg: #0E0B1A;
      --text-title: #1A1A2E;
      --text-body: #3A3A4A;
      --text-muted: #6B6B7B;
      --card-shadow: 0 2px 12px rgba(14,11,26,0.06);
      --card-hover-shadow: 0 8px 24px rgba(123,47,247,0.12);
      --border-light: #E8E6F0;
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
      --font-mono: "DIN Alternate", "PingFang SC", sans-serif;
      --section-gap: 100px;
      --container-max: 1200px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

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

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }

    h1, h2, h3, h4 {
      color: var(--text-title);
      font-weight: 600;
    }

    h1 {
      font-size: 36px;
      line-height: 1.3;
      letter-spacing: -0.5px;
      font-weight: 700;
    }

    h2 {
      font-size: 28px;
      line-height: 1.4;
    }

    h3 {
      font-size: 22px;
      line-height: 1.45;
    }

    h4 {
      font-size: 18px;
      line-height: 1.5;
      font-weight: 500;
    }

    p {
      font-size: 16px;
      line-height: 1.7;
      margin-bottom: 16px;
    }

    .text-muted {
      color: var(--text-muted);
      font-size: 14px;
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: all 0.25s ease;
      cursor: pointer;
      border: 1.5px solid transparent;
      white-space: nowrap;
    }

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

    .btn-primary:hover {
      background: var(--primary-dark);
      border-color: var(--primary-dark);
      box-shadow: 0 0 16px rgba(123,47,247,0.4);
      transform: translateY(-1px);
    }

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

    .btn-outline:hover {
      background: rgba(123,47,247,0.08);
      border-color: var(--primary-dark);
      color: var(--primary-dark);
    }

    .btn-large {
      padding: 18px 48px;
      font-size: 18px;
      border-radius: 10px;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: white;
      z-index: 1000;
      box-shadow: 0 1px 8px rgba(0,0,0,0.04);
      height: 72px;
      display: flex;
      align-items: center;
    }

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

    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--text-title);
      letter-spacing: -0.3px;
    }

    .logo span {
      color: var(--primary);
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 4px 0;
    }

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

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s ease;
    }

    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }

    .hamburger {
      display: none;
      font-size: 24px;
      background: none;
      border: none;
      color: var(--text-title);
      cursor: pointer;
    }

    /* Hero */
    .hero {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      min-height: 85vh;
      display: flex;
      align-items: center;
      margin-top: 72px;
      color: white;
    }

    .hero-overlay {
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: linear-gradient(135deg, rgba(14,11,26,0.65) 0%, rgba(123,47,247,0.45) 100%);
    }

    .hero-content {
      position: relative;
      z-index: 2;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
      width: 100%;
    }

    .hero-text h1 {
      color: white;
      font-size: 42px;
      margin-bottom: 20px;
    }

    .hero-subtitle {
      font-size: 20px;
      color: rgba(255,255,255,0.85);
      margin-bottom: 12px;
      font-weight: 400;
    }

    .hero-desc {
      color: rgba(255,255,255,0.7);
      margin-bottom: 32px;
      max-width: 480px;
    }

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

    .hero-image {
      background: url('/assets/images/coverpic/cover-1.webp') center/contain no-repeat;
      min-height: 340px;
      border-radius: 20px;
      filter: drop-shadow(0 20px 30px rgba(0,0,0,0.4));
    }

    /* 通用区块 */
    .section {
      padding: var(--section-gap) 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }

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

    .grid-2 {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }

    .card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--card-shadow);
      transition: all 0.25s ease;
    }

    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-hover-shadow);
    }

    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(123,47,247,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 22px;
    }

    /* 痛点 */
    .pain-points i {
      color: var(--accent);
      font-size: 22px;
      margin-right: 12px;
    }

    .pain-item {
      display: flex;
      align-items: flex-start;
      margin-bottom: 24px;
    }

    /* 数据面板 */
    .dark-panel {
      background: var(--deep-bg);
      color: white;
      border-radius: 24px;
      padding: 60px 40px;
      text-align: center;
    }

    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-top: 40px;
    }

    .stat-number {
      font-family: var(--font-mono);
      font-size: 48px;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }

    /* 证言 */
    .testimonial-card {
      background: #F4F2F8;
      border-radius: 12px;
      padding: 28px;
      position: relative;
    }

    .quote-mark {
      font-size: 48px;
      color: rgba(123,47,247,0.2);
      position: absolute;
      top: 10px;
      left: 18px;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
    }

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

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-body);
      line-height: 1.6;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }

    /* 页脚 */
    .footer {
      background: var(--deep-bg);
      color: #B0ADC0;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .footer a:hover {
      color: var(--accent);
    }

    .copyright {
      margin-top: 40px;
      padding-top: 20px;
      border-top: 1px solid rgba(255,255,255,0.08);
      font-size: 13px;
      color: #6B6B7B;
    }

    @media (max-width: 1024px) {
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .hero-content { grid-template-columns: 1fr; }
      .hero-image { min-height: 280px; }
    }

    @media (max-width: 768px) {
      h1 { font-size: 30px; }
      .container { padding: 0 16px; }
      .nav-links { display: none; }
      .hamburger { display: block; }
      .grid-2, .grid-3, .footer-grid { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: 1fr; }
      .hero { min-height: 70vh; }
      .section { padding: 60px 0; }
      .dark-panel { padding: 40px 20px; }
    }

    .mobile-menu {
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: rgba(14,11,26,0.95);
      backdrop-filter: blur(8px);
      padding: 32px;
      display: none;
      flex-direction: column;
      gap: 24px;
      z-index: 999;
    }

    .mobile-menu a {
      color: white;
      font-size: 18px;
    }