/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --primary-deep: #134B61;
      --accent-orange: #F4A261;
      --accent-orange-hover: #E08A4B;
      --accent-green: #2A9D8F;
      --background: #F8F9FA;
      --bg-light-blue: #F0F4F8;
      --card-bg: #FFFFFF;
      --text-deep: #2C3E50;
      --text-muted: #6B7280;
      --footer-bg: #1A3C4A;
      --border-light: rgba(0,0,0,0.05);
      --border-medium: #E5E7EB;
      --white: #FFFFFF;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.06), 0 4px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 6px 24px rgba(26,95,122,0.12);
      --shadow-btn: 0 8px 18px rgba(244,162,97,0.3);
      --transition-smooth: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    }

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

    body {
      font-family: "Inter", "PingFang SC", "Microsoft YaHei", "Noto Sans SC", system-ui, sans-serif;
      background-color: var(--background);
      color: var(--text-deep);
      line-height: 1.75;
      font-weight: 400;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
      overflow-x: hidden;
    }

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

    h1, h2, h3, h4 {
      font-weight: 700;
      line-height: 1.25;
    }

    h1 {
      font-size: clamp(2.5rem, 5vw, 4rem);
      font-weight: 800;
      letter-spacing: -0.02em;
      color: var(--primary);
    }

    h2 {
      font-size: clamp(2rem, 3.5vw, 2.75rem);
      letter-spacing: -0.01em;
      color: var(--text-deep);
      margin-bottom: 16px;
    }

    h3 {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--text-deep);
    }

    .section-gap {
      margin: 120px 0;
    }

    .bg-alt {
      background-color: var(--bg-light-blue);
      padding: 100px 0;
      margin: 120px 0;
      border-radius: 24px 24px 0 0;
    }

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

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

    a:hover {
      color: var(--accent-orange);
    }

    button, .btn {
      cursor: pointer;
      border: none;
      background: transparent;
      font-family: inherit;
      font-weight: 600;
      transition: var(--transition-smooth);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      white-space: nowrap;
      position: relative;
      overflow: hidden;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-size: 1rem;
      box-shadow: 0 2px 8px rgba(26,95,122,0.2);
    }

    .btn-primary:hover {
      background: var(--primary-deep);
      color: white;
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(26,95,122,0.3);
    }

    .btn-outline {
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 12px 30px;
      border-radius: var(--radius-sm);
      background: transparent;
    }

    .btn-outline:hover {
      background: var(--primary);
      color: white;
      transform: translateY(-2px);
    }

    .btn-accent {
      background: var(--accent-orange);
      color: white;
      padding: 14px 36px;
      border-radius: 40px;
      font-weight: 700;
      box-shadow: var(--shadow-btn);
    }

    .btn-accent:hover {
      background: var(--accent-orange-hover);
      transform: translateY(-2px);
      color: white;
    }

    .btn-accent-lg {
      padding: 18px 48px;
      font-size: 1.15rem;
      border-radius: 50px;
    }

    /* 图片占位骨架 */
    .img-placeholder {
      background: linear-gradient(135deg, #E5E7EB 20%, #F3F4F6 50%, #E5E7EB 80%);
      background-size: 200% auto;
      animation: shimmer 1.8s infinite;
    }

    @keyframes shimmer {
      0% { background-position: 100% center; }
      100% { background-position: -100% center; }
    }

    /* 导航 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 1000;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
      height: 72px;
      display: flex;
      align-items: center;
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 10px;
      letter-spacing: -0.3px;
      text-decoration: none;
    }

    .logo svg {
      width: 34px;
      height: 34px;
      stroke: var(--primary);
      fill: none;
      transition: var(--transition-smooth);
    }

    .nav-menu {
      display: flex;
      gap: 36px;
      list-style: none;
      align-items: center;
    }

    .nav-link {
      color: var(--text-deep);
      font-weight: 500;
      font-size: 1rem;
      position: relative;
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--primary);
      transition: width 0.25s ease;
    }

    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }

    .nav-link.nav-cta {
      color: var(--accent-orange);
      font-weight: 700;
    }

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

    .bar {
      width: 26px;
      height: 2px;
      background: var(--text-deep);
      transition: 0.3s;
    }

    .mobile-menu {
      display: none;
      position: absolute;
      top: 72px;
      left: 0;
      background: white;
      width: 100%;
      box-shadow: 0 8px 24px rgba(0,0,0,0.08);
      flex-direction: column;
    }

    /* Hero */
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
      min-height: 85vh;
      padding: 60px 0;
    }

    .hero-left {
      width: 52%;
    }

    .hero-subtitle {
      font-size: 1.25rem;
      color: var(--text-muted);
      margin: 20px 0 32px;
      line-height: 1.6;
      max-width: 480px;
    }

    .hero-stats {
      display: flex;
      gap: 36px;
      margin-top: 48px;
    }

    .stat-item span {
      display: block;
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--accent-orange);
    }

    .hero-right {
      width: 48%;
      height: 520px;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-hover);
      position: relative;
    }

    .hero-image {
      width: 100%;
      height: 100%;
      object-fit: cover;
      display: block;
    }

    .hero-gradient-overlay {
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: linear-gradient(135deg, rgba(26,95,122,0.3) 0%, rgba(26,95,122,0.02) 100%);
    }

    /* 亮点网格 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      margin-top: 56px;
    }

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

    .feature-card.tall {
      padding: 48px 28px;
    }

    .feature-icon {
      width: 48px;
      height: 48px;
      color: var(--primary);
      margin-bottom: 24px;
    }

    /* 瀑布流案例 */
    .cases-masonry {
      column-count: 3;
      column-gap: 24px;
      margin-top: 48px;
    }

    .case-item {
      break-inside: avoid;
      margin-bottom: 24px;
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }

    .case-cover {
      width: 100%;
      height: auto;
      aspect-ratio: 4/3;
      object-fit: cover;
    }

    .case-tag {
      background: var(--accent-green);
      color: white;
      padding: 4px 10px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
      margin: 16px 0 0 16px;
      display: inline-block;
    }

    .case-text {
      padding: 0 16px 20px;
    }

    /* 方案对比 */
    .compare-pricing {
      display: flex;
      gap: 28px;
      margin-top: 48px;
      align-items: flex-start;
    }

    .plan-card {
      background: white;
      border-radius: var(--radius-md);
      padding: 32px 24px;
      border: 2px solid transparent;
      box-shadow: var(--shadow-card);
      flex: 1;
      position: relative;
    }

    .plan-highlight {
      border: 2px solid var(--accent-orange);
      box-shadow: var(--shadow-hover);
    }

    .badge-recommend {
      position: absolute;
      top: -16px;
      right: 20px;
      background: var(--accent-orange);
      color: white;
      padding: 6px 18px;
      border-radius: 20px;
      font-weight: 600;
    }

    /* FAQ */
    .faq-split {
      display: flex;
      gap: 60px;
    }

    .faq-left {
      width: 35%;
    }

    .faq-right {
      width: 65%;
    }

    .accordion-item {
      border-bottom: 1px solid var(--border-medium);
    }

    .accordion-question {
      width: 100%;
      padding: 22px 0;
      display: flex;
      justify-content: space-between;
      font-weight: 600;
      font-size: 1.1rem;
      color: var(--text-deep);
    }

    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s;
      color: var(--text-muted);
      padding: 0 0;
    }

    .accordion-content.open {
      max-height: 250px;
      padding-bottom: 20px;
    }

    /* CTA Bar */
    .cta-full {
      background: var(--primary);
      color: white;
      text-align: center;
      padding: 80px 20px;
      border-radius: 0;
      margin-top: 0;
    }

    .footer {
      background: var(--footer-bg);
      color: rgba(255,255,255,0.8);
      padding: 70px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
      gap: 40px;
      margin-bottom: 50px;
    }

    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .cases-masonry { column-count: 2; }
    }

    @media (max-width: 768px) {
      .hamburger { display: flex; }
      .nav-menu { display: none; }
      .mobile-menu.active { display: flex; flex-direction: column; padding: 20px; }
      .hero-grid { flex-direction: column; gap: 40px; }
      .hero-left, .hero-right { width: 100%; }
      .hero-right { height: 340px; }
      .faq-split { flex-direction: column; }
      .faq-left, .faq-right { width: 100%; }
      .compare-pricing { flex-direction: column; }
      .features-grid { grid-template-columns: 1fr; }
      .cases-masonry { column-count: 1; }
      .footer-grid { grid-template-columns: repeat(2,1fr); }
    }