/* roulang page: index */
:root {
      --primary-blue: #0A1F44;
      --accent-orange: #FF4D00;
      --success-green: #00B578;
      --warning-gold: #FFB800;
      --bg-page: #F8F9FC;
      --card-white: #FFFFFF;
      --text-main: #1A1F36;
      --text-muted: #6B7280;
      --border-light: #E5E7EB;
      --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.04);
      --shadow-hover: 0 12px 28px rgba(0, 0, 0, 0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-img: 16px;
      --transition: 150ms cubic-bezier(0.2, 0.8, 0.2, 1);
    }

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

    html {
      scroll-behavior: smooth;
    }

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(255, 255, 255, 0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      transition: background 0.3s, box-shadow 0.3s;
      border-bottom: 1px solid transparent;
    }

    #header.scrolled {
      background: #FFFFFF;
      box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
      border-bottom: 1px solid rgba(0,0,0,0.02);
    }

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

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      color: var(--primary-blue);
      letter-spacing: -0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
      text-decoration: none;
    }
    .logo i {
      color: var(--accent-orange);
      font-size: 2rem;
    }

    .nav-links {
      display: flex;
      gap: 2.5rem;
      list-style: none;
      align-items: center;
    }

    .nav-links a {
      text-decoration: none;
      color: var(--text-main);
      font-weight: 500;
      font-size: 1rem;
      transition: color 0.2s, font-weight 0.2s;
      position: relative;
      padding: 0.25rem 0;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-orange);
      font-weight: 600;
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary-blue);
      cursor: pointer;
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: white;
      flex-direction: column;
      padding: 1.5rem 2rem;
      box-shadow: 0 20px 30px rgba(0,0,0,0.05);
      gap: 1.5rem;
      list-style: none;
      z-index: 99;
      backdrop-filter: blur(20px);
      background: rgba(255,255,255,0.98);
    }
    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 600;
      color: var(--primary-blue);
      text-decoration: none;
    }

    /* Hero */
    #hero {
      padding: 140px 0 100px;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }
    .hero-left h1 {
      font-size: 48px;
      font-weight: 800;
      line-height: 1.2;
      color: var(--primary-blue);
      margin-bottom: 1.5rem;
    }
    .hero-left .highlight {
      color: var(--accent-orange);
      font-size: 56px;
      display: inline-block;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-muted);
      margin-bottom: 2rem;
      max-width: 90%;
    }
    .stats-row {
      display: flex;
      gap: 2.5rem;
      margin: 2rem 0 2.5rem;
    }
    .stat b {
      font-size: 2.2rem;
      color: var(--accent-orange);
      display: block;
      font-weight: 700;
    }
    .stat span {
      font-size: 0.95rem;
      color: var(--text-muted);
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      font-weight: 600;
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
      transition: background 0.2s, transform 0.2s;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      background: #E04400;
      transform: scale(1.02);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary-blue);
      color: var(--primary-blue);
      font-weight: 600;
      padding: 0.8rem 2rem;
      border-radius: var(--radius-btn);
      text-decoration: none;
      transition: 0.2s;
      display: inline-flex;
      align-items: center;
      gap: 0.5rem;
    }
    .btn-outline:hover {
      background: rgba(10,31,68,0.05);
    }
    .hero-right .image-box {
      border-radius: var(--radius-img);
      overflow: hidden;
      box-shadow: 0 20px 35px rgba(0,0,0,0.1);
      background: #ddd;
    }
    .hero-right img {
      width: 100%;
      display: block;
      object-fit: cover;
    }

    /* 通用板块 */
    section {
      padding: 90px 0;
    }
    .section-title {
      font-size: 36px;
      font-weight: 700;
      color: var(--primary-blue);
      margin-bottom: 1rem;
      line-height: 1.3;
    }
    .section-sub {
      color: var(--text-muted);
      font-size: 1.1rem;
      margin-bottom: 3rem;
    }

    /* 亮点网格 */
    #features .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--card-white);
      border-radius: var(--radius-card);
      padding: 2rem 1.5rem;
      display: flex;
      gap: 1.25rem;
      align-items: flex-start;
      box-shadow: var(--shadow-sm);
      transition: all var(--transition);
      border: 1px solid rgba(0,0,0,0.02);
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .feature-card i {
      font-size: 2rem;
      color: var(--accent-orange);
      width: 40px;
      text-align: center;
    }
    .feature-card h3 {
      font-size: 1.3rem;
      font-weight: 600;
      margin-bottom: 0.5rem;
      color: var(--primary-blue);
    }
    .feature-card p {
      color: var(--text-muted);
      font-size: 0.95rem;
    }

    /* 案例瀑布流 */
    #showcase .masonry {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.2s;
      display: flex;
      flex-direction: column;
    }
    .case-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      height: 200px;
      overflow: hidden;
    }
    .case-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }
    .case-info {
      padding: 1.2rem 1.5rem;
    }
    .case-info h4 {
      font-weight: 700;
      font-size: 1.1rem;
      margin-bottom: 0.5rem;
    }
    .badge {
      background: rgba(255,184,0,0.15);
      color: #b45309;
      padding: 0.25rem 0.8rem;
      border-radius: 20px;
      font-size: 0.75rem;
      font-weight: 600;
      display: inline-block;
    }

    /* 方案对比 */
    .plans-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .plan-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 2rem 1.8rem;
      box-shadow: var(--shadow-sm);
      border: 1px solid transparent;
      transition: 0.25s;
      text-align: center;
    }
    .plan-card.recommended {
      border: 2px solid var(--accent-orange);
      position: relative;
    }
    .plan-card h3 {
      font-size: 1.8rem;
      color: var(--primary-blue);
    }
    .price {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--accent-orange);
      margin: 0.8rem 0;
    }
    .plan-features {
      list-style: none;
      margin: 1.5rem 0;
      color: var(--text-muted);
    }
    .plan-features li {
      margin: 0.6rem 0;
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
    }
    .faq-item {
      background: white;
      border-radius: var(--radius-card);
      padding: 1.5rem;
      box-shadow: var(--shadow-sm);
    }
    .faq-item h4 {
      font-weight: 700;
      color: var(--primary-blue);
      margin-bottom: 0.6rem;
    }

    /* 联系 */
    #contact {
      background: var(--primary-blue);
      color: white;
    }
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: start;
    }
    .contact-form input, .contact-form textarea {
      width: 100%;
      padding: 0.9rem;
      margin-bottom: 1rem;
      border-radius: var(--radius-btn);
      border: 1px solid var(--border-light);
      background: white;
      color: var(--text-main);
      font-family: inherit;
    }
    .contact-form input:focus {
      border-color: var(--primary-blue);
      box-shadow: 0 0 0 4px rgba(10,31,68,0.1);
      outline: none;
    }

    footer {
      background: white;
      padding: 2.5rem 0;
      text-align: center;
      color: var(--text-muted);
    }

    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .masonry { grid-template-columns: repeat(2,1fr); }
      .plans-grid { grid-template-columns: 1fr; max-width: 400px; margin:0 auto; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .mobile-menu.show { display: flex; }
      #hero { padding: 120px 0 60px; }
      .hero-left h1 { font-size: 32px; }
      .faq-grid { grid-template-columns: 1fr; }
      .contact-grid { grid-template-columns: 1fr; }
      .masonry { grid-template-columns: 1fr; }
      .features-grid { grid-template-columns: 1fr; }
    }