/* roulang page: index */
:root {
      --primary-400: #0D9488;
      --primary-500: #0F766E;
      --primary-700: #134E4A;
      --accent-400: #F59E0B;
      --accent-500: #D97706;
      --gray-50: #F8FAFC;
      --gray-100: #F1F5F9;
      --gray-200: #E2E8F0;
      --gray-400: #94A3B8;
      --gray-500: #64748B;
      --gray-700: #334155;
      --gray-900: #1E293B;
      --white: #FFFFFF;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --radius-xl: 20px;
      --shadow-sm: 0 4px 14px rgba(0,0,0,0.06);
      --shadow-md: 0 12px 28px rgba(0,0,0,0.1);
      --shadow-glow: 0 0 20px rgba(245,158,11,0.5);
      --font-sans: "Inter", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
      --transition: all 0.25s ease;
    }

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

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

    body {
      font-family: var(--font-sans);
      background-color: var(--gray-50);
      color: var(--gray-700);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      letter-spacing: -0.02em;
    }

    h1 {
      font-size: clamp(2.6rem, 5vw, 3.5rem);
      line-height: 1.2;
    }

    h2 {
      font-size: clamp(2rem, 4vw, 2.5rem);
      margin-bottom: 1rem;
    }

    h3 {
      font-size: 1.5rem;
      font-weight: 600;
    }

    p {
      color: var(--gray-500);
    }

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

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

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

    .btn-primary {
      background: linear-gradient(135deg, var(--primary-400), var(--primary-500));
      color: white;
      border-radius: var(--radius-md);
      padding: 14px 32px;
      box-shadow: 0 8px 18px rgba(13,148,136,0.25);
    }

    .btn-primary:hover {
      background: linear-gradient(135deg, var(--primary-500), var(--primary-700));
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary-400);
      color: var(--primary-400);
      border-radius: var(--radius-md);
      padding: 14px 32px;
    }

    .btn-outline:hover {
      background: rgba(13,148,136,0.05);
      border-color: var(--primary-500);
      color: var(--primary-500);
    }

    .btn-accent {
      background: linear-gradient(135deg, var(--accent-400), var(--accent-500));
      color: white;
      border-radius: var(--radius-md);
      padding: 14px 32px;
      font-weight: 700;
    }

    .btn-accent:hover {
      background: var(--accent-500);
      box-shadow: var(--shadow-glow);
    }

    .section {
      padding: 90px 0;
    }

    .section-title {
      text-align: center;
      margin-bottom: 3rem;
    }

    .section-title h2 {
      background: linear-gradient(135deg, var(--primary-400), var(--primary-700));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      display: inline-block;
    }

    .text-gradient {
      background: linear-gradient(135deg, var(--primary-400), var(--accent-400));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

/* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      padding: 16px 0;
      background: rgba(255,255,255,0.75);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(255,255,255,0.3);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
      transition: var(--transition);
    }

    .navbar.scrolled {
      background: rgba(13,148,136,0.96);
      backdrop-filter: blur(16px);
      border-bottom: none;
      box-shadow: 0 4px 24px 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 32px;
    }

    .logo {
      font-size: 1.4rem;
      font-weight: 700;
      color: var(--gray-700);
      display: flex;
      align-items: center;
      gap: 8px;
      transition: var(--transition);
    }

    .logo-icon {
      width: 24px;
      height: 24px;
      background: linear-gradient(135deg, var(--primary-400), var(--primary-700));
      border-radius: 6px;
      display: inline-block;
    }

    .navbar.scrolled .logo {
      color: white;
    }

    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--gray-700);
      position: relative;
      padding: 4px 0;
    }

    .navbar.scrolled .nav-links a {
      color: rgba(255,255,255,0.9);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent-400);
      transition: width 0.25s ease;
    }

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

    .nav-cta {
      background: var(--accent-400);
      color: white !important;
      padding: 10px 22px;
      border-radius: 30px;
      font-weight: 600;
    }

    .navbar.scrolled .nav-cta {
      background: var(--accent-400);
      color: white !important;
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
    }

    .hamburger span {
      width: 26px;
      height: 2px;
      background: var(--gray-700);
      transition: var(--transition);
    }

    .navbar.scrolled .hamburger span {
      background: white;
    }

    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: rgba(13,148,136,0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 2rem;
        gap: 1.5rem;
        transform: translateY(-150%);
        transition: 0.35s ease;
        box-shadow: var(--shadow-md);
      }
      .nav-links.active {
        transform: translateY(0);
      }
      .hamburger {
        display: flex;
      }
      .nav-links a {
        color: white !important;
        font-size: 1.2rem;
      }
    }

.hero {
      padding: 160px 0 100px;
      background: linear-gradient(180deg, #F0FDFA 0%, var(--white) 100%);
      display: flex;
      align-items: center;
    }

    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
    }

    .hero-left h1 {
      margin-bottom: 1.2rem;
    }

    .hero-left p {
      font-size: 1.2rem;
      margin-bottom: 2rem;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .dashboard-card {
      background: var(--gray-900);
      border-radius: 24px;
      padding: 24px;
      box-shadow: 0 20px 35px rgba(0,0,0,0.2);
      color: white;
      animation: float 5s ease-in-out infinite;
      transform: rotate(1deg);
    }

    @keyframes float {
      0% { transform: translateY(0px) rotate(1deg); }
      50% { transform: translateY(-8px) rotate(0.5deg); }
      100% { transform: translateY(0px) rotate(1deg); }
    }

    .metric-row {
      display: flex;
      justify-content: space-between;
      margin: 16px 0;
    }

    .metric {
      font-size: 1.5rem;
      font-weight: 700;
      color: #34D399;
    }

    .gold {
      color: var(--accent-400);
    }

    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        text-align: center;
      }
      .hero-buttons {
        justify-content: center;
      }
    }

.features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .feature-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--gray-200);
      transition: var(--transition);
    }

    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
    }

    .feature-icon {
      font-size: 2.2rem;
      margin-bottom: 1rem;
    }

    .badge-number {
      font-size: 2rem;
      font-weight: 800;
      margin-top: 1rem;
      background: linear-gradient(135deg, var(--primary-400), var(--accent-400));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }

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

.product-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }

    .product-row.reverse {
      flex-direction: row-reverse;
    }

    .product-text {
      flex: 1;
    }

    .product-text h3 {
      margin-bottom: 1rem;
    }

    .decor-line {
      width: 48px;
      height: 3px;
      background: linear-gradient(to right, var(--primary-400), var(--accent-400));
      margin-bottom: 1.5rem;
    }

    .product-image {
      flex: 1;
      background: var(--gray-200);
      border-radius: var(--radius-xl);
      height: 300px;
      background-size: cover;
      background-position: center;
      position: relative;
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }

    .product-image::after {
      content: "";
      position: absolute;
      inset: 0;
      background: rgba(0,0,0,0.2);
    }

    @media (max-width: 768px) {
      .product-row, .product-row.reverse {
        flex-direction: column;
      }
    }

.solutions-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .solution-card {
      background: white;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }

    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }

    .solution-img {
      height: 180px;
      background-size: cover;
      background-position: center;
    }

    .solution-content {
      padding: 20px;
    }

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

.faq-item {
      background: white;
      border-bottom: 1px solid var(--gray-200);
      padding: 20px;
      position: relative;
      cursor: pointer;
    }

    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: 0.3s ease;
      color: var(--gray-500);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 16px;
    }

    .faq-item.active::before {
      content: '';
      position: absolute;
      left: 0;
      top: 0;
      height: 100%;
      width: 4px;
      background: var(--primary-400);
    }