/* roulang page: index */
:root {
      --primary-deep: #0B0E2D;
      --primary-accent: #FF5E3A;
      --bg-light: #F5F7FC;
      --card-white: #FFFFFF;
      --text-main: #1A1D36;
      --text-muted: #5A5D6E;
      --border-light: #E9EBF0;
      --shadow-sm: 0 4px 12px rgba(0, 0, 0, 0.04);
      --shadow-card: 0 8px 24px rgba(0, 0, 0, 0.06);
      --shadow-hover: 0 16px 32px rgba(0, 0, 0, 0.12);
      --radius-lg: 16px;
      --radius-xl: 24px;
      --radius-btn: 40px;
      --font-heading: 'PingFang SC', 'Noto Sans SC', 'Inter', system-ui, -apple-system, sans-serif;
      --font-body: 'PingFang SC', 'Inter', system-ui, -apple-system, sans-serif;
      --font-mono: 'DIN Alternate', 'SF Mono', 'Inter', monospace;
      --transition: all 0.25s ease;
      --nav-blur: rgba(11, 14, 45, 0.92);
    }

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

    body {
      font-family: var(--font-body);
      background-color: var(--bg-light);
      color: var(--text-main);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

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

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

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

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 导航 PC */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 999;
      transition: background 0.3s ease, backdrop-filter 0.3s;
      padding: 16px 0;
    }
    .header.scrolled {
      background: var(--nav-blur);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-family: var(--font-heading);
      font-weight: 800;
      font-size: 1.8rem;
      color: #FFFFFF;
      letter-spacing: 1px;
      background: linear-gradient(135deg, #FFFFFF 0%, #E0E7FF 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      text-shadow: 0 2px 10px rgba(0,0,0,0.2);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      color: rgba(255,255,255,0.85);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-accent);
      transition: width 0.25s;
    }
    .nav-links a:hover {
      color: #FFFFFF;
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--primary-accent);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 0.95rem;
      box-shadow: 0 6px 18px rgba(255, 94, 58, 0.3);
    }
    .btn-primary:hover {
      filter: brightness(1.1);
      transform: scale(1.02);
      box-shadow: 0 10px 24px rgba(255, 94, 58, 0.45);
    }
    .btn-outline {
      border: 2px solid var(--primary-deep);
      color: var(--primary-deep);
      background: transparent;
      padding: 10px 26px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--primary-deep);
      color: white;
      border-color: var(--primary-deep);
    }

    /* 移动端底部导航 */
    .mobile-nav {
      display: none;
      position: fixed;
      bottom: 16px;
      left: 50%;
      transform: translateX(-50%);
      width: calc(100% - 32px);
      max-width: 420px;
      background: rgba(11, 14, 45, 0.95);
      backdrop-filter: blur(20px);
      border-radius: 48px;
      padding: 8px 16px;
      box-shadow: 0 12px 32px rgba(0,0,0,0.25);
      z-index: 1000;
      justify-content: space-around;
      align-items: center;
    }
    .mobile-nav a {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: rgba(255,255,255,0.7);
      font-size: 0.7rem;
      font-weight: 500;
      gap: 4px;
    }
    .mobile-nav a i {
      font-size: 1.4rem;
    }
    .mobile-nav .center-btn {
      background: var(--primary-accent);
      border-radius: 40px;
      padding: 12px 20px;
      color: white;
      font-weight: 700;
      box-shadow: 0 8px 20px rgba(255,94,58,0.5);
      margin-top: -20px;
    }

    /* Hero */
    .hero {
      background: var(--primary-deep);
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      padding-top: 80px;
    }
    .starfield {
      position: absolute;
      top:0; left:0; width:100%; height:100%;
      background: radial-gradient(circle at 30% 40%, rgba(255,94,58,0.08) 0%, transparent 50%);
    }
    .orbit {
      position: absolute;
      top: 20%; left: 70%;
      width: 500px; height: 500px;
      border: 1px dashed rgba(255,255,255,0.15);
      border-radius: 50%;
      animation: spin 36s linear infinite;
    }
    @keyframes spin { to { transform: rotate(360deg); } }
    .hero-content {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-family: var(--font-heading);
      font-size: clamp(3rem, 7vw, 4.5rem);
      font-weight: 900;
      color: white;
      line-height: 1.1;
      margin-bottom: 20px;
    }
    .hero-text .highlight {
      color: var(--primary-accent);
    }
    .hero-sub {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
    }
    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero-image img {
      max-height: 420px;
      border-radius: 24px;
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    }

    /* 通用板块 */
    section {
      padding: 80px 0;
    }
    .section-title {
      font-family: var(--font-heading);
      font-size: 2.4rem;
      font-weight: 800;
      text-align: center;
      margin-bottom: 16px;
    }
    .section-sub {
      text-align: center;
      color: var(--text-muted);
      max-width: 600px;
      margin: 0 auto 48px;
    }

    /* 功能网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(6, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--card-white);
      border-radius: var(--radius-lg);
      padding: 28px 16px;
      text-align: center;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      font-size: 2.5rem;
      color: var(--primary-accent);
      margin-bottom: 16px;
    }
    .feature-card h3 {
      font-weight: 700;
      margin-bottom: 8px;
    }

    /* 场景卡片 */
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .scene-card {
      background: var(--card-white);
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .scene-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .scene-img {
      height: 200px;
      overflow: hidden;
    }
    .scene-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .scene-card:hover .scene-img img {
      transform: scale(1.04);
    }
    .scene-text {
      padding: 20px;
    }

    /* 深色案例 */
    .dark-section {
      background: var(--primary-deep);
      color: white;
    }
    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 40px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-mono);
      font-size: 3rem;
      font-weight: 700;
      color: var(--primary-accent);
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      align-items: start;
    }
    .pricing-card {
      background: white;
      border-radius: var(--radius-xl);
      padding: 32px;
      box-shadow: var(--shadow-card);
      text-align: center;
    }
    .pricing-card.featured {
      border: 2px solid var(--primary-accent);
      transform: scale(1.03);
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: var(--radius-lg);
      margin-bottom: 16px;
      box-shadow: var(--shadow-sm);
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-answer {
      padding: 0 24px 20px;
      display: none;
    }
    .faq-item.active .faq-answer {
      display: block;
    }

    /* CTA 横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #FF5E3A 0%, #FF7A4D 100%);
      border-radius: 32px;
      padding: 64px 40px;
      text-align: center;
      color: white;
    }

    footer {
      background: #0B0E2D;
      color: #CCD0E0;
      padding: 60px 0 30px;
    }

    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: repeat(3, 1fr); }
      .scenarios-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .header { display: none; }
      .mobile-nav { display: flex; }
      .hero { min-height: auto; padding: 120px 0 40px; }
      .hero-content { flex-direction: column; }
      .features-grid { grid-template-columns: repeat(2, 1fr); }
      .scenarios-grid { grid-template-columns: 1fr; }
      .pricing-grid { grid-template-columns: 1fr; }
      .nav-links { display: none; }
    }