/* roulang page: index */
:root {
      --primary-dark: #1a1a1a;
      --primary-charcoal: #2c2c2c;
      --accent-signal: #a3e635;
      --bg-white: #ffffff;
      --bg-light: #f8f9fa;
      --text-body: #343a40;
      --text-muted: #495057;
      --text-heading: #1a1a1a;
      --border-light: rgba(0,0,0,0.06);
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 20px rgba(0,0,0,0.08);
      --shadow-hover: 0 14px 28px rgba(0,0,0,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --transition: all 0.25s ease;
    }

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

    body {
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      font-weight: 400;
      line-height: 1.7;
      color: var(--text-body);
      background-color: var(--bg-white);
      -webkit-font-smoothing: antialiased;
    }

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

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

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

    /* 导航栏 - 分屏联动风格 */
    .k1-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      background: rgba(255,255,255,0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      box-shadow: 0 1px 0 var(--border-light);
      z-index: 99;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 32px;
    }

    .logo-area a {
      font-weight: 700;
      font-size: 1.8rem;
      letter-spacing: -0.02em;
      color: var(--primary-dark);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo-area span {
      font-weight: 800;
    }

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

    .nav-links li a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--primary-dark);
      padding: 0.25rem 0;
      border-bottom: 2px solid transparent;
      transition: var(--transition);
      letter-spacing: 0.01em;
    }

    .nav-links li a:hover,
    .nav-links li a.active {
      border-bottom-color: var(--accent-signal);
      color: #000;
    }

    .mobile-menu-trigger {
      display: none;
      font-size: 1.6rem;
      color: var(--primary-dark);
      background: none;
      border: none;
      cursor: pointer;
    }

    /* Hero 分栏布局 */
    .hero-section {
      padding: 160px 0 100px;
      display: flex;
      flex-wrap: wrap;
      align-items: center;
      min-height: 85vh;
      background: var(--bg-white);
    }
    .hero-left {
      flex: 0 0 55%;
      padding-right: 3rem;
    }
    .hero-right {
      flex: 0 0 45%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      min-height: 480px;
      border-radius: 24px;
      box-shadow: var(--shadow-md);
      position: relative;
    }

    .hero-left h1 {
      font-weight: 800;
      font-size: 4.2rem;
      letter-spacing: -0.02em;
      line-height: 1.15;
      color: var(--text-heading);
      margin-bottom: 1.8rem;
    }
    .hero-left .subhead {
      font-size: 1.25rem;
      color: var(--text-muted);
      line-height: 1.6;
      margin-bottom: 2.2rem;
      max-width: 85%;
    }
    .btn-primary {
      background: var(--accent-signal);
      color: #0f172a;
      font-weight: 700;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      border: none;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 4px 12px rgba(163,230,53,0.25);
      letter-spacing: 0.5px;
    }
    .btn-primary:hover {
      filter: brightness(1.08);
      box-shadow: 0 8px 24px rgba(163,230,53,0.35);
      transform: translateY(-2px);
      color: #0f172a;
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-weight: 700;
      font-size: 2.6rem;
      letter-spacing: -0.01em;
      margin-bottom: 1.2rem;
      color: var(--text-heading);
    }
    .section-sub {
      font-size: 1.15rem;
      color: var(--text-muted);
      margin-bottom: 3rem;
    }

    /* 能力卡片 不对称网格 */
    .competence-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .comp-card {
      background: var(--bg-white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .comp-card.large {
      grid-column: span 2;
    }
    .comp-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .comp-icon {
      font-size: 2.2rem;
      color: var(--accent-signal);
      margin-bottom: 1.2rem;
    }
    .comp-card h3 {
      font-weight: 600;
      font-size: 1.5rem;
      margin-bottom: 0.5rem;
    }

    /* 案例瀑布流 */
    .portfolio-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 24px;
    }
    .case-card {
      flex: 1 1 calc(33.333% - 24px);
      background: var(--bg-white);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--border-light);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      min-width: 260px;
    }
    .case-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
    }
    .case-img {
      height: 220px;
      background-size: cover;
      background-position: center;
    }
    .case-content {
      padding: 24px;
    }
    .case-tag {
      font-size: 0.75rem;
      font-weight: 700;
      text-transform: uppercase;
      letter-spacing: 0.08em;
      color: #0f172a;
      background: var(--accent-signal);
      display: inline-block;
      padding: 4px 10px;
      border-radius: 20px;
      margin-bottom: 0.8rem;
    }

    /* 方法论对比 */
    .method-compare {
      display: flex;
      gap: 32px;
      align-items: stretch;
      flex-wrap: wrap;
    }
    .method-box {
      flex: 1;
      padding: 32px;
      border-radius: var(--radius-card);
      background: var(--bg-light);
      border: 1px solid var(--border-light);
    }
    .method-box.k1 {
      background: var(--primary-dark);
      color: white;
      border-color: var(--primary-dark);
    }
    .method-box h4 {
      font-weight: 700;
      margin-bottom: 1rem;
    }

    /* FAQ */
    .accordion-faq .accordion-item {
      border-bottom: 1px solid var(--border-light);
      margin-bottom: 8px;
    }
    .accordion-title {
      font-weight: 700;
      font-size: 1.2rem;
      padding: 1.2rem 0;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }

    /* CTA 区域 */
    .cta-section {
      background: linear-gradient(135deg, #1e1e1e 0%, #111 100%);
      color: white;
      border-radius: 28px;
      padding: 64px 48px;
      margin: 60px 0;
    }
    .cta-form input, .cta-form textarea {
      width: 100%;
      padding: 12px;
      border-radius: 6px;
      border: 1px solid #444;
      background: #2a2a2a;
      color: white;
      margin-bottom: 16px;
    }
    .btn-outline-light {
      border: 2px solid var(--accent-signal);
      background: transparent;
      color: var(--accent-signal);
      font-weight: 700;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
    }

    footer {
      background: var(--primary-dark);
      color: #ccc;
      padding: 60px 0 30px;
      margin-top: 40px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    @media (max-width: 1024px) {
      .hero-left { flex: 0 0 50%; }
      .hero-right { flex: 0 0 50%; min-height: 360px; }
      .competence-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-trigger { display: block; }
      .hero-section { flex-direction: column; padding-top: 100px; }
      .hero-left, .hero-right { flex: 1 1 100%; padding-right: 0; }
      .hero-right { min-height: 300px; margin-top: 32px; }
      .footer-grid { grid-template-columns: 1fr; }
      .case-card { flex: 1 1 100%; }
    }