/* roulang page: index */
:root {
      --primary-gradient: linear-gradient(135deg, #FF5F1F 0%, #FF8C42 100%);
      --primary-orange: #FF5F1F;
      --primary-hover: #E64A1A;
      --deep-black: #1A1A1A;
      --accent-red: #E63946;
      --gray-bg: #F0F2F5;
      --white: #FFFFFF;
      --text-main: #1F2937;
      --text-secondary: #4B5563;
      --text-light: #9CA3AF;
      --border-light: #E5E7EB;
      --shadow-card: 0 8px 30px rgba(0, 0, 0, 0.06);
      --shadow-hover: 0 20px 40px rgba(0, 0, 0, 0.12);
      --radius-card: 20px;
      --radius-btn: 50px;
      --font-hero: 48px;
      --font-section: 36px;
      --font-card-title: 22px;
      --font-base: 16px;
      --transition-smooth: all 0.3s cubic-bezier(0.2, 0.9, 0.4, 1);
    }

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

    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: #FAFBFC;
      color: var(--text-main);
      line-height: 1.6;
      scroll-behavior: smooth;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--white);
      z-index: 1000;
      height: 72px;
      border-bottom: 1px solid transparent;
      transition: var(--transition-smooth);
      display: flex;
      align-items: center;
    }

    .navbar.scrolled {
      border-bottom: 1px solid var(--border-light);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      text-decoration: none;
      color: var(--deep-black);
      font-weight: 700;
      font-size: 1.8rem;
      letter-spacing: -0.5px;
    }

    .logo-icon {
      font-size: 2rem;
      color: var(--primary-orange);
    }

    .nav-links {
      display: flex;
      gap: 2.5rem;
      align-items: center;
    }

    .nav-links a {
      text-decoration: none;
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 1rem;
      transition: color 0.2s;
      white-space: nowrap;
    }

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

    .btn-primary-nav {
      background: var(--primary-gradient);
      color: white !important;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      box-shadow: 0 4px 12px rgba(255,95,31,0.3);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 10px;
      z-index: 1001;
    }

    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--deep-black);
      border-radius: 2px;
      transition: var(--transition-smooth);
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10, 12, 16, 0.95);
      backdrop-filter: blur(12px);
      z-index: 999;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 2.5rem;
    }

    .mobile-menu a {
      color: white;
      font-size: 1.8rem;
      font-weight: 600;
      text-decoration: none;
    }

    /* Hero区域 */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 0% 50%, #1F2833, #0B0C10);
      position: relative;
      overflow: hidden;
      padding: 100px 0 60px;
    }

    .hero::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 400"><path d="M0,200 L400,200" stroke="rgba(255,95,31,0.15)" stroke-width="2"/><circle cx="50" cy="200" r="6" fill="%23FF5F1F" opacity="0.4"/><circle cx="200" cy="120" r="10" fill="%23E63946" opacity="0.5"/></svg>');
      animation: floatParticles 10s infinite alternate;
    }

    @keyframes floatParticles {
      0% { transform: translateY(0px); opacity: 0.6; }
      100% { transform: translateY(-30px); opacity: 1; }
    }

    .hero-content {
      display: flex;
      align-items: center;
      gap: 3rem;
      position: relative;
      z-index: 2;
      width: 100%;
    }

    .hero-left {
      flex: 1;
      color: white;
    }

    .hero-left h1 {
      font-size: 54px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.5rem;
      color: white;
    }

    .hero-left .highlight {
      background: var(--primary-gradient);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .hero-desc {
      font-size: 1.25rem;
      color: rgba(255,255,255,0.8);
      margin-bottom: 2.5rem;
      max-width: 500px;
    }

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

    .btn-primary {
      background: var(--primary-gradient);
      border: none;
      color: white;
      font-weight: 700;
      padding: 16px 40px;
      border-radius: var(--radius-btn);
      cursor: pointer;
      transition: var(--transition-smooth);
      box-shadow: 0 8px 20px rgba(255,95,31,0.5);
    }

    .btn-primary:hover {
      filter: brightness(1.1);
      transform: translateY(-3px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      font-weight: 700;
      padding: 16px 40px;
      border-radius: var(--radius-btn);
      cursor: pointer;
      transition: var(--transition-smooth);
    }

    .btn-outline:hover {
      background: rgba(255,255,255,0.15);
    }

    .hero-metrics {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .metric-badge {
      background: rgba(255,255,255,0.1);
      backdrop-filter: blur(12px);
      border-radius: 16px;
      padding: 18px 24px;
      min-width: 130px;
      animation: float 3.5s infinite alternate;
    }

    @keyframes float {
      0% { transform: translateY(0); }
      100% { transform: translateY(-8px); }
    }

    .metric-value {
      font-size: 38px;
      font-weight: 800;
      color: var(--primary-orange);
    }

    /* 区块通用 */
    section {
      padding: 100px 0;
    }

    .section-title {
      font-size: var(--font-section);
      font-weight: 700;
      text-align: center;
      margin-bottom: 1rem;
    }

    .section-sub {
      text-align: center;
      color: var(--text-secondary);
      margin-bottom: 3rem;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }

    .card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 36px 28px;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }

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

    .price-card.highlight {
      border: 2px solid var(--primary-orange);
      background: #FFF9F3;
    }

    /* Footer */
    .footer {
      background: #0B0C10;
      color: #9CA3AF;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-content { flex-direction: column; }
      .grid-3 { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .hero-left h1 { font-size: 38px; }
    }