/* roulang page: index */
/* ----- 设计变量与全局重置 ----- */
    :root {
      --primary: #2B6FF2;
      --primary-hover: #1A5AE0;
      --accent: #FF5C35;
      --accent-hover: #E04A2A;
      --accent-glow: rgba(255, 92, 53, 0.35);
      --bg-light: #F7F8FA;
      --bg-white: #FFFFFF;
      --bg-dark: #0F172A;
      --text-main: #1E293B;
      --text-secondary: #64748B;
      --text-muted: #94A3B8;
      --text-on-dark: #F1F5F9;
      --success: #10B981;
      --border-light: #E2E8F0;
      --radius-xl: 24px;
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --shadow-card: 0 8px 24px rgba(0,0,0,0.04);
      --shadow-hover: 0 18px 36px rgba(0,0,0,0.08);
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', 'SF Pro Display', 'PingFang SC', sans-serif;
      --transition: 0.25s ease;
      --max-width: 1280px;
    }

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

    html {
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }

    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: var(--bg-white);
      line-height: 1.8;
      font-weight: 400;
      font-size: 16px;
      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: var(--font-body);
      border: none;
      background: none;
      transition: var(--transition);
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }

    /* ----- 导航栏 (PC透明→滚动白底) ----- */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      height: 72px;
      display: flex;
      align-items: center;
      transition: background 0.3s ease, box-shadow 0.3s ease;
      background: transparent;
    }

    .main-header.scrolled {
      background: var(--bg-white);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }

    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }

    .logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 22px;
      letter-spacing: -0.3px;
      color: #fff;
      transition: color 0.3s;
      white-space: nowrap;
    }
    .main-header.scrolled .logo {
      color: var(--text-main);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      font-weight: 500;
      font-size: 15px;
    }
    .nav-links a {
      color: rgba(255,255,255,0.9);
      position: relative;
      padding: 4px 0;
    }
    .main-header.scrolled .nav-links a {
      color: var(--text-secondary);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent);
    }

    .btn-nav-cta {
      background: var(--accent);
      color: #fff !important;
      padding: 10px 22px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 14px;
      box-shadow: 0 6px 18px var(--accent-glow);
    }
    .btn-nav-cta:hover {
      background: var(--accent-hover);
      transform: scale(1.03);
    }

    /* 移动端底部胶囊导航 */
    .mobile-bottom-nav {
      display: none;
    }

    @media (max-width: 1023px) {
      .main-header {
        background: var(--bg-white);
        box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      }
      .main-header .logo {
        color: var(--text-main);
      }
      .nav-links {
        display: none;
      }
      .mobile-bottom-nav {
        display: flex;
        position: fixed;
        bottom: 16px;
        left: 50%;
        transform: translateX(-50%);
        width: calc(100% - 40px);
        max-width: 420px;
        background: rgba(255,255,255,0.85);
        backdrop-filter: blur(20px);
        border-radius: 40px;
        padding: 8px 16px;
        justify-content: space-around;
        align-items: center;
        box-shadow: 0 10px 30px rgba(0,0,0,0.1);
        z-index: 1001;
      }
      .mobile-nav-item {
        display: flex;
        flex-direction: column;
        align-items: center;
        font-size: 12px;
        color: var(--text-secondary);
        font-weight: 500;
        transition: color 0.2s;
      }
      .mobile-nav-item.active {
        color: var(--accent);
      }
      .mobile-nav-icon {
        font-size: 20px;
        margin-bottom: 2px;
      }
    }

    /* ----- 通用区块间距 ----- */
    section {
      padding: 120px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 80px 0;
      }
    }

    /* ----- Hero 首屏 ----- */
    .hero {
      height: 100vh;
      min-height: 700px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      display: flex;
      align-items: center;
      color: #fff;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(90deg, rgba(15,23,42,0.7) 0%, rgba(15,23,42,0.3) 100%);
    }
    .hero-content {
      position: relative;
      max-width: 700px;
    }
    .hero h1 {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 52px;
      line-height: 1.2;
      letter-spacing: -0.02em;
      margin-bottom: 20px;
    }
    .hero .subtitle {
      font-size: 18px;
      opacity: 0.9;
      margin-bottom: 36px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent);
      color: #fff;
      padding: 16px 36px;
      border-radius: 12px;
      font-weight: 600;
      font-size: 16px;
      box-shadow: 0 10px 25px var(--accent-glow);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      transform: scale(1.04);
    }
    .btn-outline {
      border: 2px solid rgba(255,255,255,0.8);
      color: #fff;
      padding: 16px 36px;
      border-radius: 12px;
      font-weight: 600;
      background: transparent;
    }
    .btn-outline:hover {
      background: #fff;
      color: var(--text-main);
    }

    @media (max-width: 768px) {
      .hero h1 {
        font-size: 36px;
      }
    }

    /* 痛点区 */
    .pain-grid {
      display: flex;
      gap: 48px;
      margin-top: 48px;
    }
    .pain-item {
      display: flex;
      gap: 24px;
      align-items: flex-start;
    }
    .pain-num {
      font-size: 48px;
      font-weight: 700;
      color: var(--primary);
      opacity: 0.2;
      line-height: 1;
    }
    @media (max-width: 768px) {
      .pain-grid {
        flex-direction: column;
      }
    }

    /* 方案区非对称 */
    .solution-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 64px;
      align-items: center;
    }
    .solution-img img {
      border-radius: var(--radius-xl);
    }
    @media (max-width: 1023px) {
      .solution-row {
        grid-template-columns: 1fr;
      }
    }

    /* 成果数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 32px;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 56px;
      font-weight: 700;
      color: var(--success);
    }
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    /* 证言卡片 */
    .testimonials-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
    }
    .testimonial-card {
      min-width: 300px;
      background: #fff;
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-card);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    details {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    summary {
      font-weight: 600;
      cursor: pointer;
      list-style: none;
    }

    /* CTA深色区 */
    .dark-cta {
      background: var(--bg-dark);
      color: #fff;
    }
    .btn-download {
      background: var(--accent);
      color: #fff;
      padding: 18px 40px;
      border-radius: 40px;
      font-weight: 700;
    }

    /* 页脚 */
    .footer {
      background: var(--bg-dark);
      color: #94A3B8;
      padding: 48px 0;
    }