/* roulang page: index */
/* ----- 设计变量 & 全局重置 ----- */
    :root {
      --deep-space: #0A0E27;
      --bg-gradient-end: #0D1333;
      --electric-cyan: #00E5FF;
      --electric-cyan-dark: #00BCD4;
      --aurora-purple: #7C4DFF;
      --aurora-purple-hover: #651FFF;
      --text-white: #F0F4FF;
      --text-gray-blue: #B0C4DE;
      --text-soft: #8899AA;
      --card-bg: rgba(255, 255, 255, 0.03);
      --card-border: rgba(255, 255, 255, 0.08);
      --card-border-hover: rgba(0, 229, 255, 0.3);
      --glass-blur: blur(20px);
      --border-radius-card: 20px;
      --border-radius-btn: 12px;
      --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);
      --shadow-glow: 0 0 30px rgba(0, 229, 255, 0.25);
      --transition-smooth: 0.35s ease;
      --container-max: 1280px;
      --section-gap-desktop: 140px;
      --section-gap-mobile: 80px;
    }

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

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

    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background: linear-gradient(170deg, var(--deep-space) 0%, #0D1333 100%);
      color: var(--text-gray-blue);
      line-height: 1.7;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
    }

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

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.25s;
    }

    /* 标题全局风格 */
    h1, h2, h3, h4 {
      color: var(--text-white);
      font-weight: 700;
      line-height: 1.25;
      letter-spacing: -0.01em;
    }

    h1 {
      font-size: clamp(2.5rem, 7vw, 4rem);
      font-weight: 800;
      letter-spacing: -0.02em;
      line-height: 1.15;
    }

    h2 {
      font-size: clamp(2rem, 5vw, 2.75rem);
      margin-bottom: 1.2rem;
    }

    h3 {
      font-size: 1.4rem;
      font-weight: 600;
    }

    /* 按钮系统 */
    .btn-primary {
      background: linear-gradient(135deg, var(--electric-cyan), var(--electric-cyan-dark));
      color: #0A0E27;
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--border-radius-btn);
      border: none;
      cursor: pointer;
      font-size: 1rem;
      transition: all 0.3s ease;
      box-shadow: 0 0 20px rgba(0, 229, 255, 0.25);
      display: inline-block;
      text-align: center;
      letter-spacing: 0.3px;
    }

    .btn-primary:hover {
      box-shadow: 0 0 40px rgba(0, 229, 255, 0.55);
      transform: scale(1.04);
      background: linear-gradient(135deg, #00F0FF, #00D4E8);
      color: #0A0E27;
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid rgba(0, 229, 255, 0.4);
      color: var(--electric-cyan);
      padding: 14px 36px;
      border-radius: var(--border-radius-btn);
      font-weight: 600;
      transition: all 0.3s ease;
      display: inline-block;
      text-align: center;
      cursor: pointer;
    }

    .btn-outline:hover {
      background: rgba(0, 229, 255, 0.08);
      border-color: var(--electric-cyan);
      box-shadow: 0 0 20px rgba(0, 229, 255, 0.2);
      color: #fff;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: var(--glass-blur);
      -webkit-backdrop-filter: var(--glass-blur);
      border: 1px solid var(--card-border);
      border-radius: var(--border-radius-card);
      padding: 32px;
      box-shadow: var(--shadow-card);
      transition: all var(--transition-smooth);
    }

    .glass-card:hover {
      border-color: var(--card-border-hover);
      box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4), 0 0 28px rgba(0, 229, 255, 0.12);
      transform: translateY(-5px);
    }

    /* 装饰性光晕 */
    .glow-orb {
      position: absolute;
      border-radius: 50%;
      filter: blur(70px);
      opacity: 0.08;
      pointer-events: none;
      z-index: 0;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(10, 14, 39, 0.78);
      backdrop-filter: blur(18px);
      -webkit-backdrop-filter: blur(18px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.06);
      z-index: 100;
      transition: background 0.3s;
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }

    .brand {
      font-size: 1.9rem;
      font-weight: 700;
      color: #fff;
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .brand span {
      background: linear-gradient(135deg, var(--electric-cyan), var(--aurora-purple));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .nav-menu {
      display: flex;
      gap: 2.2rem;
      align-items: center;
    }
    .nav-link {
      color: var(--text-gray-blue);
      font-weight: 500;
      font-size: 0.95rem;
      transition: color 0.2s;
      position: relative;
    }
    .nav-link:hover,
    .nav-link.active {
      color: #fff;
    }

    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: #fff;
      background: none;
      border: none;
      cursor: pointer;
    }

    /* Hero */
    .hero {
      position: relative;
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-attachment: fixed;
      margin-top: 0;
      overflow: hidden;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(180deg, rgba(10,14,39,0.65) 0%, rgba(10,14,39,0.88) 100%);
      z-index: 1;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 750px;
      padding: 160px 0 100px;
    }
    .hero h1 {
      background: linear-gradient(135deg, #00E5FF, #7C4DFF);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      margin-bottom: 1.2rem;
    }
    .hero-sub {
      font-size: 1.25rem;
      color: #cbd5e1;
      margin-bottom: 1rem;
    }
    .hero-pain {
      color: var(--text-soft);
      margin-bottom: 2.2rem;
      font-size: 1.05rem;
      border-left: 3px solid var(--aurora-purple);
      padding-left: 1.2rem;
    }

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

    .section-header {
      text-align: center;
      margin-bottom: 3.5rem;
    }
    .section-header p {
      color: var(--text-gray-blue);
      max-width: 600px;
      margin: 0.6rem auto 0;
    }

    /* 痛点卡片 (无发光悬停，沉稳) */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .pain-card {
      background: rgba(255,255,255,0.02);
      border: 1px solid rgba(255,255,255,0.05);
      border-radius: 24px;
      padding: 32px 24px;
      text-align: center;
    }
    .icon-circle {
      width: 64px;
      height: 64px;
      background: rgba(0,229,255,0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin: 0 auto 20px;
      font-size: 2rem;
      color: var(--electric-cyan);
    }

    /* 解决方案网格 */
    .solution-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 28px;
    }

    /* 数据成果 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
      text-align: center;
    }
    .stat-number {
      font-size: 3.2rem;
      font-weight: 800;
      color: var(--aurora-purple);
      line-height: 1;
      margin-bottom: 0.4rem;
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
    }
    .testimonial-card {
      background: rgba(255,255,255,0.02);
      border-left: 4px solid var(--electric-cyan);
      padding: 28px;
      border-radius: 16px;
      position: relative;
    }
    .quote-icon {
      font-size: 2.5rem;
      color: rgba(124, 77, 255, 0.3);
      position: absolute;
      top: 10px;
      left: 16px;
    }

    /* FAQ 手风琴 */
    .faq-item {
      background: rgba(255,255,255,0.02);
      backdrop-filter: blur(10px);
      border: 1px solid rgba(255,255,255,0.04);
      border-radius: 16px;
      margin-bottom: 14px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: #fff;
      font-size: 1.1rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      background: rgba(0,0,0,0.2);
      color: var(--text-gray-blue);
      padding: 0 24px;
    }
    .faq-item.active .faq-answer {
      max-height: 160px;
      padding: 16px 24px;
    }
    .faq-toggle {
      font-size: 1.4rem;
      color: var(--electric-cyan);
    }

    /* CTA 区块 */
    .cta-section {
      background: #040712;
      text-align: center;
      padding: 90px 0;
    }

    .footer {
      background: #060A14;
      color: var(--text-soft);
      padding: 36px 0;
      font-size: 0.9rem;
      border-top: 1px solid rgba(255,255,255,0.04);
    }
    .footer-content {
      display: flex;
      justify-content: space-between;
      align-items: center;
      flex-wrap: wrap;
      gap: 16px;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .solution-grid { grid-template-columns: repeat(2, 1fr); }
      .pain-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .testimonial-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .hamburger { display: block; }
      .nav-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: rgba(8, 12, 26, 0.96);
        backdrop-filter: blur(25px);
        flex-direction: column;
        padding: 32px 24px;
        gap: 24px;
        transform: translateY(-120%);
        transition: transform 0.4s ease;
        border-bottom: 1px solid rgba(255,255,255,0.1);
      }
      .nav-menu.active {
        transform: translateY(0);
      }
      .pain-grid, .solution-grid, .stats-grid {
        grid-template-columns: 1fr;
      }
      section {
        padding: var(--section-gap-mobile) 0;
      }
      .hero-content {
        padding: 130px 0 70px;
      }
    }