/* roulang page: index */
:root {
      --primary-deep: #0A0E27;
      --accent-red: #FF4655;
      --accent-cyan: #00E5FF;
      --bg-light: #F5F6FA;
      --text-dark: #1E2A3A;
      --text-muted: #5A6577;
      --text-light: #B0B7C3;
      --white: #FFFFFF;
      --border-light: #D0D5DD;
      --shadow-card: 0 4px 24px rgba(10, 14, 39, 0.06);
      --shadow-hover: 0 12px 32px rgba(255, 70, 85, 0.15);
      --radius-card: 16px;
      --radius-btn: 50px;
      --radius-badge: 8px;
      --transition: all 0.3s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-mono: "Inter", "Roboto", "SF Mono", monospace;
      --container-max: 1280px;
    }

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

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

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

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

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

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

    h1, h2, h3, h4 {
      font-weight: 700;
    }

    h1 {
      font-size: 48px;
      font-weight: 900;
      line-height: 1.2;
      letter-spacing: -0.5px;
    }

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

    h3 {
      font-size: 22px;
      font-weight: 600;
      margin-bottom: 8px;
    }

    section {
      padding: 100px 0;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--white);
      z-index: 1000;
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
      transition: var(--transition);
    }

    .header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.06);
    }

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

    .logo {
      font-size: 28px;
      font-weight: 800;
      letter-spacing: -0.3px;
      color: var(--primary-deep);
    }
    .logo span {
      color: var(--accent-cyan);
    }

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

    .nav-links a {
      font-weight: 500;
      font-size: 16px;
      color: var(--text-dark);
      position: relative;
    }

    .nav-links a:hover {
      color: var(--accent-red);
    }

    .nav-cta {
      background: var(--accent-red);
      color: var(--white);
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      margin-left: 16px;
      transition: var(--transition);
    }
    .nav-cta:hover {
      background: #E03342;
      transform: scale(1.03);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      cursor: pointer;
      gap: 5px;
    }
    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--primary-deep);
      border-radius: 4px;
      transition: var(--transition);
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--white);
      flex-direction: column;
      padding: 32px 24px;
      box-shadow: 0 10px 25px rgba(0,0,0,0.1);
      gap: 20px;
      z-index: 999;
      border-top: 1px solid #eee;
    }
    .mobile-menu a {
      font-size: 20px;
      font-weight: 600;
      color: var(--text-dark);
    }

    /* Hero */
    .hero {
      background: linear-gradient(135deg, #0A0E27 0%, #1A1F3A 60%, #FF4655 150%);
      color: var(--white);
      padding: 160px 0 100px;
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: "";
      position: absolute;
      right: -10%;
      top: 10%;
      width: 500px;
      height: 500px;
      background: rgba(255,70,85,0.15);
      transform: rotate(45deg);
      border-radius: 80px;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1;
    }
    .hero h1 {
      color: var(--white);
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-light);
      margin-bottom: 40px;
      max-width: 550px;
    }
    .hero-btns {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-red);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-size: 16px;
    }
    .btn-primary:hover {
      background: #E03342;
      transform: scale(1.03);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--accent-cyan);
      color: var(--accent-cyan);
      padding: 14px 36px;
      border-radius: var(--radius-btn);
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.08);
    }
    .hero-image {
      flex: 1;
      border-radius: 24px;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    }

    /* 区块标题 */
    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      display: inline-block;
      background: linear-gradient(135deg, var(--primary-deep), var(--accent-red));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .section-title p {
      color: var(--text-muted);
      font-size: 18px;
      max-width: 650px;
      margin: 0 auto;
    }

    /* 卡片网格 */
    .grid-3, .grid-4 {
      display: grid;
      gap: 30px;
    }
    .grid-3 { grid-template-columns: repeat(3, 1fr); }
    .grid-4 { grid-template-columns: repeat(4, 1fr); }

    .card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 1px solid transparent;
      display: flex;
      flex-direction: column;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent-cyan);
    }
    .card-icon {
      font-size: 36px;
      margin-bottom: 20px;
    }
    .card h3 {
      color: var(--primary-deep);
    }
    .card p {
      color: var(--text-muted);
      margin-bottom: 20px;
      flex: 1;
    }
    .badge {
      background: rgba(10,14,39,0.08);
      color: var(--accent-cyan);
      font-family: var(--font-mono);
      font-weight: 700;
      padding: 6px 14px;
      border-radius: var(--radius-badge);
      font-size: 14px;
      align-self: flex-start;
      background: #0A0E27;
    }

    .scenario-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .scenario-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .scenario-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }
    .scenario-content {
      padding: 24px;
    }

    .case-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
    }
    .case-cover {
      height: 200px;
      background-size: cover;
    }
    .case-body {
      padding: 24px;
    }
    .case-stat {
      display: flex;
      gap: 16px;
      margin-top: 12px;
    }

    .pricing-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 40px 30px;
      text-align: center;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      border: 2px solid transparent;
    }
    .pricing-card.featured {
      border-color: var(--accent-red);
      transform: scale(1.03);
      box-shadow: var(--shadow-hover);
    }
    .price {
      font-size: 42px;
      font-weight: 800;
      color: var(--primary-deep);
      margin: 20px 0;
    }

    /* FAQ */
    .faq-item {
      background: var(--white);
      border-radius: 12px;
      margin-bottom: 16px;
      border: 1px solid #E4E8EE;
      overflow: hidden;
    }
    .faq-question {
      padding: 24px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
    }
    .faq-answer {
      padding: 0 24px 24px;
      color: var(--text-muted);
      display: none;
    }
    .faq-item.active {
      border-color: var(--accent-cyan);
    }
    .faq-item.active .faq-answer {
      display: block;
    }

    .cta-banner {
      background: linear-gradient(90deg, #FF4655, #00E5FF);
      padding: 80px 0;
      text-align: center;
      color: white;
    }

    .footer {
      background: var(--primary-deep);
      color: var(--text-light);
      padding: 70px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a:hover {
      color: var(--accent-red);
    }

    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      h1 { font-size: 32px; }
      h2 { font-size: 28px; }
      .hero .container { flex-direction: column; }
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .grid-3, .grid-4 { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .pricing-card.featured { transform: none; }
    }