/* roulang page: index */
/* ----- 全局变量与基础重置 ----- */
    :root {
      --deep-space: #0B0C1E;
      --electric-cyan: #00F0FF;
      --neon-violet: #A855F7;
      --nebula-gray: #1E1F2E;
      --light-gray-bg: #F0F1F5;
      --white: #FFFFFF;
      --gray-text: #CBD5E1;
      --dark-text: #334155;
      --muted-text: #94A3B8;
      --border-glow: rgba(0, 240, 255, 0.15);
      --card-shadow: 0 4px 24px rgba(0,0,0,0.25);
      --hover-shadow: 0 8px 40px rgba(0,240,255,0.2);
      --btn-shadow: 0 0 18px rgba(0,240,255,0.4);
      --radius-lg: 20px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-xs: 8px;
      --section-padding: 5rem 1.5rem;
      --container-max: 1280px;
      --transition: all 0.3s ease;
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: 'Inter', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      background-color: var(--deep-space);
      color: var(--gray-text);
      line-height: 1.6;
      font-weight: 400;
      -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;
      font-family: inherit;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 1.5rem;
      width: 100%;
    }

    /* 渐变文字工具 */
    .gradient-text {
      background: linear-gradient(135deg, var(--electric-cyan), var(--neon-violet));
      -webkit-background-clip: text;
      background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    /* ----- 导航区 Header / Nav ----- */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(11,12,30,0.88);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,240,255,0.2);
      z-index: 1000;
      padding: 0.75rem 0;
      transition: background 0.3s;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 1.5rem;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      color: var(--white);
      display: flex;
      align-items: center;
      gap: 0.25rem;
    }
    .logo i {
      color: var(--electric-cyan);
      font-size: 2rem;
    }
    .logo span {
      background: linear-gradient(135deg, #fff, #bae6ff);
      -webkit-background-clip: text;
      background-clip: text;
      -webkit-text-fill-color: transparent;
    }

    .nav-links {
      display: flex;
      gap: 2rem;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      color: var(--gray-text);
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding-bottom: 6px;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--electric-cyan);
      transition: width 0.3s ease;
    }

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

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

    .nav-cta {
      background: linear-gradient(135deg, var(--electric-cyan), var(--neon-violet));
      color: white !important;
      padding: 0.6rem 1.8rem;
      border-radius: 30px;
      font-weight: 600;
      box-shadow: var(--btn-shadow);
      transition: transform 0.2s, box-shadow 0.2s;
    }
    .nav-cta:hover {
      transform: scale(1.04);
      box-shadow: 0 0 25px rgba(0,240,255,0.6);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--electric-cyan);
      border-radius: 4px;
      transition: 0.3s;
    }

    @media (max-width: 900px) {
      .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 100%;
        background: rgba(11,12,30,0.96);
        backdrop-filter: blur(24px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: 0.4s ease;
        gap: 2.5rem;
        z-index: 999;
      }
      .nav-links.active {
        right: 0;
      }
      .nav-links a {
        font-size: 1.6rem;
        font-weight: 600;
      }
      .hamburger {
        display: flex;
        z-index: 1001;
      }
    }

    /* ----- Hero 首屏 ----- */
    .hero {
      padding: 10rem 0 6rem;
      display: flex;
      align-items: center;
      min-height: 90vh;
      background: radial-gradient(circle at 20% 20%, rgba(168,85,247,0.08), transparent 60%);
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 2.5rem;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 400px;
    }
    .hero-text h1 {
      font-size: clamp(2.2rem, 5.5vw, 3.8rem);
      font-weight: 800;
      color: var(--white);
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }
    .hero-text p {
      font-size: 1.2rem;
      color: #CBD5E1;
      margin-bottom: 2rem;
      max-width: 550px;
    }
    .hero-buttons {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--electric-cyan), var(--neon-violet));
      color: white;
      padding: 0.9rem 2.2rem;
      border-radius: 40px;
      font-weight: 700;
      border: none;
      box-shadow: 0 0 20px rgba(0,240,255,0.4);
      transition: 0.3s;
      font-size: 1rem;
    }
    .btn-primary:hover {
      background: linear-gradient(135deg, var(--neon-violet), var(--electric-cyan));
      box-shadow: 0 0 28px rgba(168,85,247,0.6);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--electric-cyan);
      color: var(--electric-cyan);
      padding: 0.9rem 2.2rem;
      border-radius: 40px;
      font-weight: 600;
      transition: 0.3s;
    }
    .btn-outline:hover {
      background: rgba(0,240,255,0.1);
      border-color: white;
      color: white;
    }
    .hero-image {
      flex: 1 1 400px;
      display: flex;
      justify-content: center;
      animation: float 4s ease-in-out infinite;
    }
    .hero-image img {
      border-radius: 28px;
      box-shadow: 0 0 40px rgba(0,240,255,0.25);
      max-height: 460px;
      object-fit: cover;
      border: 1px solid rgba(255,255,255,0.1);
    }
    @keyframes float {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-12px); }
    }

    /* 星空粒子背景点缀 */
    .stars {
      position: absolute;
      width: 100%;
      height: 100%;
      top:0;
      left:0;
      pointer-events: none;
    }
    .star {
      position: absolute;
      background: white;
      border-radius: 50%;
      opacity: 0.7;
      animation: pulse 2s infinite;
    }

    /* ----- 区块标题 ----- */
    .section-title {
      font-size: clamp(1.8rem, 4vw, 2.6rem);
      font-weight: 700;
      color: var(--white);
      margin-bottom: 0.8rem;
      text-align: center;
    }
    .section-sub {
      color: var(--muted-text);
      text-align: center;
      max-width: 700px;
      margin: 0 auto 3.5rem;
      font-size: 1.1rem;
    }

    /* ----- 核心优势（非对称）----- */
    .advantages-grid {
      display: grid;
      grid-template-columns: 1.3fr 0.7fr;
      gap: 1.8rem;
    }
    .adv-left {
      background: rgba(30,31,46,0.7);
      backdrop-filter: blur(8px);
      border-radius: 24px;
      padding: 2.2rem;
      border: 1px solid var(--border-glow);
      display: flex;
      flex-direction: column;
    }
    .adv-right {
      display: flex;
      flex-direction: column;
      gap: 1.8rem;
    }
    .adv-card {
      background: rgba(30,31,46,0.6);
      backdrop-filter: blur(8px);
      border-radius: 20px;
      padding: 1.6rem;
      border: 1px solid rgba(255,255,255,0.05);
    }
    .badge-number {
      font-size: 2.3rem;
      font-weight: 800;
      color: var(--electric-cyan);
    }
    .icon-wrap {
      font-size: 2rem;
      color: var(--electric-cyan);
      margin-bottom: 1rem;
    }

    @media (max-width: 768px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }

    /* ----- 功能矩阵 2x3 ----- */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 2rem;
    }
    .feature-card {
      background: rgba(30,31,46,0.65);
      backdrop-filter: blur(6px);
      border-radius: 20px;
      padding: 2rem 1.5rem;
      border: 1px solid rgba(0,240,255,0.15);
      transition: 0.3s;
    }
    .feature-card:hover {
      border-color: var(--electric-cyan);
      box-shadow: 0 0 28px rgba(0,240,255,0.3);
      transform: translateY(-4px);
    }
    @media (max-width: 900px) {
      .features-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 520px) {
      .features-grid { grid-template-columns: 1fr; }
    }

    /* ----- 场景卡片 ----- */
    .scenes-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 2rem;
    }
    .scene-card {
      background: #141529;
      border-radius: 22px;
      overflow: hidden;
    }
    .scene-img img {
      height: 180px;
      object-fit: cover;
      width: 100%;
    }
    .scene-content {
      padding: 1.5rem;
    }
    .gradient-bar {
      height: 4px;
      background: linear-gradient(90deg, var(--electric-cyan), var(--neon-violet));
      margin-top: 1rem;
      border-radius: 2px;
    }
    @media (max-width: 768px) {
      .scenes-grid { grid-template-columns: 1fr; }
    }

    /* ----- 案例卡片 ----- */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 2rem;
    }
    .case-card {
      background: rgba(30,31,46,0.7);
      backdrop-filter: blur(8px);
      border-radius: 20px;
      padding: 1.8rem;
      display: flex;
      border:1px solid rgba(255,255,255,0.05);
    }
    @media (max-width: 700px) {
      .cases-grid { grid-template-columns: 1fr; }
    }

    /* FAQ */
    .faq-item {
      background: #1a1b2e;
      margin-bottom: 1rem;
      border-radius: 16px;
      overflow: hidden;
    }
    .faq-question {
      padding: 1.4rem 2rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: white;
    }
    /* CTA 全宽 */
    .cta-section {
      background: linear-gradient(135deg, #0f0f23, #1b1130);
      padding: 5rem 1.5rem;
      text-align: center;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 2.5rem;
    }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 480px) {
      .footer-grid { grid-template-columns: 1fr; }
    }
    .footer a:hover { color: var(--electric-cyan); }