/* roulang page: index */
:root {
      --primary-deep: #0B1A1A;
      --accent-cyan: #00E5A0;
      --accent-cyan-hover: #1AFFB3;
      --platinum: #C0C8D0;
      --bg-dark: #0F1115;
      --bg-card: #1A1D24;
      --text-main: #E5E9F0;
      --text-secondary: #8F9BB0;
      --border-dim: rgba(192, 200, 208, 0.1);
      --border-hover: #00E5A0;
      --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.4);
      --radius-md: 12px;
      --radius-btn: 8px;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
      --transition: 0.3s ease;
      --container-max: 1280px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-dark);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    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: all var(--transition);
      border-radius: var(--radius-btn);
    }
    h1, h2, h3 {
      font-weight: 700;
      line-height: 1.2;
    }
    h1 {
      font-size: 56px;
      font-weight: 800;
      letter-spacing: -0.02em;
    }
    h2 {
      font-size: 40px;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 24px;
      font-weight: 600;
    }
    .text-accent {
      color: var(--accent-cyan);
    }
    .bg-card {
      background-color: var(--bg-card);
      border: 1px solid var(--border-dim);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
    }
    /* 导航 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      height: 72px;
      background: rgba(15, 17, 21, 0.85);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-dim);
      display: flex;
      align-items: center;
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      background: linear-gradient(135deg, #00E5A0 0%, #7BFFCC 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: -0.5px;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: var(--platinum);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 8px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: width var(--transition);
    }
    .nav-links a:hover, .nav-links a.active {
      color: var(--accent-cyan);
    }
    .nav-links a:hover::after, .nav-links a.active::after {
      width: 100%;
    }
    .mobile-menu-toggle {
      display: none;
      background: none;
      border: none;
      color: var(--platinum);
      font-size: 1.8rem;
    }
    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 16px;
      left: 50%;
      transform: translateX(-50%);
      width: calc(100% - 32px);
      max-width: 420px;
      background: rgba(26, 29, 36, 0.9);
      backdrop-filter: blur(16px);
      border-radius: 24px;
      padding: 8px 16px;
      z-index: 110;
      border: 1px solid var(--border-dim);
      box-shadow: 0 8px 30px rgba(0,0,0,0.6);
    }
    .mobile-bottom-nav-inner {
      display: flex;
      align-items: center;
      justify-content: space-around;
    }
    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: var(--platinum);
      font-size: 0.7rem;
      font-weight: 500;
      gap: 4px;
      padding: 6px 10px;
      border-radius: 16px;
      transition: 0.2s;
    }
    .mobile-nav-item i {
      font-size: 1.3rem;
    }
    .mobile-nav-item.active {
      color: var(--accent-cyan);
    }
    .mobile-cta-circle {
      background: var(--accent-cyan);
      color: #0B1A1A;
      width: 44px;
      height: 44px;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.3rem;
      margin-top: -20px;
      box-shadow: 0 0 16px rgba(0,229,160,0.5);
    }
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding-top: 72px;
      position: relative;
      overflow: hidden;
      background: radial-gradient(circle at 80% 20%, rgba(0,229,160,0.06) 0%, var(--bg-dark) 70%);
    }
    .hero-grid-bg {
      position: absolute;
      inset: 0;
      background-image: linear-gradient(rgba(192,200,208,0.03) 1px, transparent 1px), linear-gradient(90deg, rgba(192,200,208,0.03) 1px, transparent 1px);
      background-size: 40px 40px;
      pointer-events: none;
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-left {
      flex: 1;
    }
    .hero-right {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero h1 {
      color: white;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--platinum);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .btn-group {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-cyan);
      color: #0B1A1A;
      padding: 14px 32px;
      font-weight: 600;
    }
    .btn-primary:hover {
      background: var(--accent-cyan-hover);
      box-shadow: 0 0 20px rgba(0,229,160,0.4);
    }
    .btn-outline {
      border: 1px solid var(--accent-cyan);
      color: var(--accent-cyan);
      padding: 14px 32px;
      background: transparent;
    }
    .btn-outline:hover {
      background: rgba(0,229,160,0.1);
    }
    .particle-circle {
      width: 300px;
      height: 300px;
      border: 2px dashed rgba(0,229,160,0.4);
      border-radius: 50%;
      position: relative;
      animation: spin 20s linear infinite;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .particle-circle::before {
      content: '';
      width: 12px;
      height: 12px;
      background: var(--accent-cyan);
      border-radius: 50%;
      position: absolute;
      top: -6px;
      box-shadow: 0 0 25px #00E5A0;
    }
    @keyframes spin { 100% { transform: rotate(360deg); } }
    .scroll-indicator {
      position: absolute;
      bottom: 20px;
      left: 50%;
      transform: translateX(-50%);
      color: var(--accent-cyan);
      font-size: 1.5rem;
      animation: bounce 2s infinite;
    }
    @keyframes bounce { 0%,100%{transform:translateY(0);}50%{transform:translateY(10px);} }
    /* 通用板块 */
    section {
      padding: 100px 0;
    }
    .section-label {
      font-size: 0.9rem;
      color: var(--accent-cyan);
      text-transform: uppercase;
      letter-spacing: 2px;
      margin-bottom: 8px;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    .pain-point .big-number {
      font-size: 5rem;
      font-weight: 800;
      color: rgba(0,229,160,0.15);
      line-height: 1;
    }
    .solution-steps {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .step-item {
      padding-left: 20px;
      border-left: 3px solid var(--border-dim);
      transition: 0.2s;
    }
    .step-item.active {
      border-left-color: var(--accent-cyan);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .stat-card {
      background: var(--bg-card);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      text-align: center;
      border:1px solid var(--border-dim);
    }
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--accent-cyan);
    }
    .testimonial-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 10px;
      scroll-snap-type: x mandatory;
    }
    .testimonial-card {
      min-width: 300px;
      background: var(--bg-card);
      border-radius: var(--radius-md);
      padding: 28px;
      border:1px solid var(--border-dim);
      scroll-snap-align: start;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-dim);
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--platinum);
    }
    .cta-section {
      background: radial-gradient(circle at center, rgba(0,229,160,0.08) 0%, var(--bg-dark) 70%);
      text-align: center;
    }
    footer {
      background: var(--primary-deep);
      padding: 60px 0 30px;
      color: var(--platinum);
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      h1 { font-size: 42px; }
      h2 { font-size: 32px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-toggle { display: block; }
      .mobile-bottom-nav { display: block; }
      .grid-2, .footer-grid { grid-template-columns: 1fr; }
      .hero-content { flex-direction: column; }
      .hero { text-align: center; }
      .stats-grid { grid-template-columns: 1fr; }
      section { padding: 60px 0; }
      h1 { font-size: 36px; }
    }