/* roulang page: index */
:root {
      --primary: #0B2B26;
      --accent: #E85D04;
      --bg-light: #F7F8FA;
      --white: #FFFFFF;
      --text-dark: #1E293B;
      --text-muted: #64748B;
      --border-light: rgba(0,0,0,0.05);
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 24px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: 0.25s ease;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", "Inter", system-ui, -apple-system, sans-serif;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      font-family: var(--font-sans);
      background: var(--bg-light);
      color: var(--text-dark);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--white);
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
      height: 68px;
      display: flex;
      align-items: center;
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: 0.5px;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--accent);
      font-weight: 800;
    }
    .nav-links {
      display: flex;
      gap: 2.5rem;
      align-items: center;
      font-weight: 500;
      color: #334155;
    }
    .nav-links a {
      transition: color 0.2s;
      font-size: 0.95rem;
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      background: none;
      border: none;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary);
      border-radius: 2px;
    }
    /* Hero */
    .hero {
      background: var(--white);
      padding: 3rem 0 4rem;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 3rem;
      align-items: center;
    }
    .hero-content h1 {
      font-size: 2.5rem;
      font-weight: 700;
      line-height: 1.3;
      color: var(--primary);
      margin-bottom: 1rem;
    }
    .hero-content p {
      font-size: 1.1rem;
      color: var(--text-muted);
      margin-bottom: 2rem;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 0.85rem 2.2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      transition: filter 0.2s, transform 0.1s;
      display: inline-block;
    }
    .btn-primary:hover {
      filter: brightness(1.12);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      padding: 0.75rem 2rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.2s;
      display: inline-block;
    }
    .btn-outline:hover {
      background: rgba(11,43,38,0.06);
    }
    .hero-image {
      background: linear-gradient(135deg, rgba(11,43,38,0.1) 0%, rgba(232,93,4,0.08) 100%);
      border-radius: 24px;
      overflow: hidden;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .hero-image img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    /* 板块标题 */
    .section-title {
      font-size: 2rem;
      font-weight: 650;
      color: var(--primary);
      margin-bottom: 0.5rem;
    }
    .section-sub {
      color: var(--text-muted);
      margin-bottom: 2.5rem;
    }
    /* 亮点网格 2x3 */
    .advantages {
      padding: 4rem 0;
    }
    .grid-2x3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .adv-card {
      background: var(--white);
      padding: 2rem 1.5rem;
      border-radius: var(--radius-card);
      transition: all var(--transition);
      border: 1px solid transparent;
      position: relative;
    }
    .adv-card:hover {
      box-shadow: var(--shadow-hover);
      border-color: rgba(0,0,0,0.02);
      transform: translateY(-4px);
    }
    .adv-card::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 4px;
      background: transparent;
      transition: background 0.2s;
    }
    .adv-card:hover::after {
      background: var(--accent);
    }
    .adv-icon {
      font-size: 2.2rem;
      color: var(--accent);
      margin-bottom: 1.2rem;
    }
    .adv-card h3 {
      font-size: 1.25rem;
      margin-bottom: 0.5rem;
    }
    /* 数据条 */
    .trust-bar {
      background: var(--primary);
      color: white;
      padding: 2.5rem 0;
      margin: 2rem 0;
    }
    .stats {
      display: flex;
      justify-content: space-around;
      text-align: center;
      flex-wrap: wrap;
      gap: 2rem;
    }
    .stat-number {
      font-size: 2.4rem;
      font-weight: 700;
      color: var(--accent);
    }
    /* 案例瀑布流 */
    .cases {
      padding: 4rem 0;
    }
    .waterfall {
      columns: 3;
      column-gap: 1.5rem;
    }
    .case-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      margin-bottom: 1.5rem;
      break-inside: avoid;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-card img {
      width: 100%;
      display: block;
    }
    .case-text {
      padding: 1.2rem;
    }
    .case-text h3 {
      font-size: 1.1rem;
      margin-bottom: 0.25rem;
    }
    .tag {
      display: inline-block;
      background: rgba(232,93,4,0.1);
      color: var(--accent);
      font-size: 0.75rem;
      padding: 0.2rem 0.7rem;
      border-radius: 20px;
      font-weight: 600;
      margin-right: 0.5rem;
    }
    /* 方案对比 */
    .comparison {
      padding: 4rem 0;
      background: var(--white);
    }
    .compare-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.5rem;
    }
    .compare-col {
      background: #F9FAFB;
      border-radius: var(--radius-card);
      padding: 2rem 1.5rem;
    }
    .compare-col.highlight {
      background: white;
      border: 1px solid var(--accent);
      position: relative;
    }
    .badge {
      background: var(--accent);
      color: white;
      font-size: 0.8rem;
      font-weight: 700;
      padding: 0.3rem 1rem;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 1rem;
    }
    .check::before { content: "✓ "; color: var(--accent); font-weight: bold; }
    .cross::before { content: "✗ "; color: #94a3b8; }
    /* FAQ */
    .faq {
      padding: 4rem 0;
    }
    .accordion-item {
      background: var(--white);
      border-radius: 10px;
      margin-bottom: 0.8rem;
      box-shadow: 0 2px 6px rgba(0,0,0,0.02);
    }
    .accordion-header {
      padding: 1.2rem 1.5rem;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      border-left: 4px solid transparent;
      transition: 0.2s;
    }
    .accordion-item.active .accordion-header {
      border-left-color: var(--accent);
      background: #f8fafc;
    }
    .accordion-body {
      padding: 0 1.5rem 1.2rem;
      display: none;
      color: #475569;
    }
    .accordion-item.active .accordion-body {
      display: block;
    }
    /* CTA */
    .global-cta {
      background: var(--primary);
      color: white;
      text-align: center;
      padding: 4rem 0;
    }
    .global-cta h2 {
      font-size: 2rem;
      margin-bottom: 1rem;
    }
    /* 页脚 */
    .footer {
      background: #0A1F1C;
      color: #cbd5e1;
      padding: 3rem 0 1.5rem;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1.5fr;
      gap: 2rem;
    }
    .footer a {
      color: #94a3b8;
      transition: color 0.2s;
    }
    .footer a:hover { color: var(--accent); }
    @media (max-width: 1024px) {
      .hero-grid { grid-template-columns: 1fr; }
      .waterfall { columns: 2; }
      .grid-2x3 { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .container { padding: 0 16px; }
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-content h1 { font-size: 2rem; }
      .grid-2x3 { grid-template-columns: 1fr; }
      .waterfall { columns: 1; }
      .compare-grid { grid-template-columns: 1fr; overflow-x: auto; }
      .footer-grid { grid-template-columns: 1fr; }
      .stats { flex-direction: column; }
    }