/* roulang page: index */
:root {
      --primary-dark: #0A0E17;
      --accent-cyan: #00F0FF;
      --accent-red: #FF3C5A;
      --bg-white: #FFFFFF;
      --bg-light: #F5F6FA;
      --text-main: #1A1A1A;
      --text-secondary: #5A5A5A;
      --text-muted: #6A7A8A;
      --border-light: #E8ECF1;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --font-mono: "Inter", "SF Mono", monospace;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 4px 20px rgba(0, 0, 0, 0.04);
      --shadow-hover: 0 12px 32px rgba(0, 0, 0, 0.08);
      --transition: 0.3s ease;
    }
    
    * {
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-sans);
      color: var(--text-main);
      background-color: var(--bg-white);
      margin: 0;
      padding: 0;
      line-height: 1.7;
      font-weight: 400;
      font-size: 16px;
      overflow-x: hidden;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    button, input, textarea {
      font-family: var(--font-sans);
    }
    
    /* 主布局：分屏结构 */
    .app-wrapper {
      display: flex;
      min-height: 100vh;
      position: relative;
    }
    
    /* 左侧固定导航面板 */
    .left-panel {
      width: 40%;
      background-color: var(--primary-dark);
      position: fixed;
      top: 0;
      left: 0;
      height: 100vh;
      display: flex;
      flex-direction: column;
      justify-content: center;
      padding: 3rem 2.5rem;
      z-index: 1000;
      background-image: url('/assets/images/backpic/hero-left.jpg');
      background-size: cover;
      background-position: center;
      background-repeat: no-repeat;
      box-shadow: 4px 0 24px rgba(0,0,0,0.2);
    }
    
    .left-panel::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: linear-gradient(135deg, rgba(10,14,23,0.92) 0%, rgba(10,14,23,0.8) 100%);
      z-index: 0;
    }
    
    .nav-content {
      position: relative;
      z-index: 2;
      display: flex;
      flex-direction: column;
      justify-content: space-between;
      height: 100%;
      max-width: 320px;
      margin-left: auto;
      margin-right: 2rem;
    }
    
    .logo-area {
      margin-bottom: 3rem;
    }
    
    .logo-text {
      font-size: 28px;
      font-weight: 700;
      color: #FFFFFF;
      letter-spacing: -0.02em;
      display: flex;
      align-items: center;
      gap: 12px;
      line-height: 1.2;
    }
    
    .logo-indicator {
      width: 8px;
      height: 32px;
      background-color: var(--accent-cyan);
      border-radius: 4px;
      display: inline-block;
    }
    
    .nav-links {
      display: flex;
      flex-direction: column;
      gap: 1.2rem;
      margin-top: 2rem;
      margin-bottom: 2rem;
    }
    
    .nav-link-item {
      color: #B0B8C5;
      font-size: 18px;
      font-weight: 500;
      padding: 0.5rem 0;
      position: relative;
      transition: color 0.2s ease, transform 0.2s ease;
      display: flex;
      align-items: center;
      gap: 12px;
    }
    
    .nav-link-item::before {
      content: '';
      width: 4px;
      height: 20px;
      background-color: transparent;
      border-radius: 2px;
      transition: background-color 0.2s ease;
    }
    
    .nav-link-item:hover {
      color: var(--accent-cyan);
      transform: translateX(4px);
    }
    
    .nav-link-item:hover::before {
      background-color: var(--accent-cyan);
    }
    
    .nav-link-item.active {
      color: #FFFFFF;
    }
    
    .nav-link-item.active::before {
      background-color: var(--accent-cyan);
    }
    
    .nav-cta {
      margin-top: auto;
    }
    
    .btn-nav-cta {
      background-color: var(--accent-red);
      color: white;
      border: none;
      padding: 0.8rem 1.8rem;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: background-color 0.2s ease, box-shadow 0.2s ease;
      text-align: center;
      display: inline-block;
      width: fit-content;
    }
    
    .btn-nav-cta:hover {
      background-color: #D52E48;
      box-shadow: 0 8px 18px rgba(255, 60, 90, 0.3);
      color: white;
    }
    
    /* 右侧内容区 */
    .right-content {
      width: 60%;
      margin-left: 40%;
      background-color: var(--bg-white);
      padding: 0 60px;
      max-width: 860px;
    }
    
    section {
      padding: 80px 0;
      min-height: auto;
    }
    
    .section-title {
      font-size: 40px;
      font-weight: 700;
      letter-spacing: -0.02em;
      line-height: 1.2;
      color: var(--text-main);
      margin-bottom: 1rem;
    }
    
    .section-subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 2.5rem;
      line-height: 1.7;
    }
    
    /* Hero */
    .hero-section {
      display: flex;
      flex-direction: column;
      justify-content: center;
      min-height: 100vh;
      padding-top: 0;
      padding-bottom: 0;
    }
    
    .hero-title {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.02em;
      color: var(--text-main);
    }
    
    .hero-subtitle {
      font-size: 20px;
      color: var(--text-secondary);
      margin: 1.5rem 0 2rem;
      max-width: 90%;
    }
    
    .hero-tags {
      display: flex;
      gap: 12px;
      flex-wrap: wrap;
    }
    
    .hero-tag {
      background-color: #F0F4FF;
      color: #00A8CC;
      padding: 0.4rem 1.2rem;
      border-radius: 30px;
      font-weight: 500;
      font-size: 14px;
    }
    
    /* 解决方案卡片 */
    .solution-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    
    .solution-card {
      background: var(--bg-white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-card);
      padding: 2.5rem 2rem;
      box-shadow: var(--shadow-sm);
      transition: transform 0.3s ease, box-shadow 0.3s ease;
      display: flex;
      flex-direction: column;
      align-items: flex-start;
    }
    
    .solution-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    
    .solution-icon {
      font-size: 48px;
      color: var(--accent-cyan);
      margin-bottom: 1.5rem;
      transition: transform 0.2s ease;
    }
    
    .solution-card:hover .solution-icon {
      transform: scale(1.05);
    }
    
    .solution-card h3 {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 0.8rem;
      color: var(--text-main);
    }
    
    .solution-card p {
      color: var(--text-secondary);
      margin: 0;
      line-height: 1.7;
    }
    
    /* 成果数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }
    
    .stat-item .stat-number {
      font-family: var(--font-mono);
      font-size: 48px;
      font-weight: 800;
      color: var(--accent-cyan);
      line-height: 1.1;
    }
    
    .stat-label {
      font-size: 16px;
      color: var(--text-secondary);
      margin-top: 0.5rem;
    }
    
    /* 证言卡片 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    
    .testimonial-card {
      background: var(--bg-light);
      border-radius: var(--radius-card);
      padding: 2rem;
      position: relative;
      border-left: 4px solid var(--accent-cyan);
      box-shadow: var(--shadow-sm);
    }
    
    .testimonial-avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      object-fit: cover;
      margin-bottom: 1rem;
    }
    
    .testimonial-text {
      font-style: italic;
      color: var(--text-main);
      margin-bottom: 1.2rem;
      line-height: 1.6;
    }
    
    .testimonial-name {
      font-weight: 700;
      color: var(--text-main);
    }
    
    .testimonial-role {
      font-size: 14px;
      color: var(--text-secondary);
    }
    
    /* FAQ 手风琴 */
    .accordion-item {
      background: transparent;
      border: none;
      border-bottom: 1px solid var(--border-light);
    }
    
    .accordion-button {
      background: #FFFFFF;
      color: var(--text-main);
      font-weight: 600;
      font-size: 18px;
      padding: 1.2rem 0;
      box-shadow: none;
      border: none;
      transition: color 0.2s;
    }
    
    .accordion-button:not(.collapsed) {
      color: var(--accent-cyan);
      background: transparent;
    }
    
    .accordion-button::after {
      transition: transform 0.2s ease;
    }
    
    .accordion-button:not(.collapsed)::after {
      transform: rotate(45deg);
    }
    
    .accordion-body {
      color: var(--text-secondary);
      padding: 0 0 1.5rem 0;
    }
    
    /* CTA 区 */
    .cta-section {
      background-color: var(--primary-dark);
      border-radius: 24px;
      padding: 3.5rem 3rem;
      color: white;
    }
    
    .cta-form input, .cta-form textarea {
      background: #1A1F2B;
      border: 1px solid transparent;
      color: white;
      padding: 0.8rem 1rem;
      border-radius: 8px;
      width: 100%;
      margin-bottom: 1rem;
      transition: border 0.2s;
    }
    
    .cta-form input:focus, .cta-form textarea:focus {
      outline: none;
      border-color: var(--accent-cyan);
      box-shadow: 0 0 0 2px rgba(0,240,255,0.2);
    }
    
    .cta-form input::placeholder, .cta-form textarea::placeholder {
      color: #6A7A8A;
    }
    
    .btn-submit {
      background-color: var(--accent-red);
      color: white;
      border: none;
      padding: 1rem 2rem;
      font-weight: 600;
      border-radius: var(--radius-btn);
      width: 100%;
      transition: background 0.2s;
    }
    
    .btn-submit:hover {
      background-color: #D52E48;
    }
    
    .contact-info {
      color: #B0B8C5;
      margin-top: 1.5rem;
    }
    
    /* 页脚 */
    footer {
      background: var(--primary-dark);
      color: #6A7A8A;
      padding: 2rem 0;
      text-align: center;
      margin-top: 80px;
    }
    
    /* 响应式 */
    @media (max-width: 1024px) {
      .right-content {
        padding: 0 40px;
      }
      .hero-title {
        font-size: 44px;
      }
    }
    
    @media (max-width: 768px) {
      .app-wrapper {
        flex-direction: column;
      }
      .left-panel {
        position: relative;
        width: 100%;
        height: auto;
        flex-direction: row;
        padding: 1rem 1.5rem;
        background-image: none;
        background-color: var(--primary-dark);
      }
      .left-panel::before {
        display: none;
      }
      .nav-content {
        flex-direction: row;
        align-items: center;
        justify-content: space-between;
        width: 100%;
        margin: 0;
        max-width: 100%;
      }
      .nav-links {
        display: none;
      }
      .logo-area {
        margin-bottom: 0;
      }
      .right-content {
        width: 100%;
        margin-left: 0;
        padding: 0 24px;
      }
      .hero-title {
        font-size: 36px;
      }
      .solution-grid, .testimonial-grid {
        grid-template-columns: 1fr;
      }
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
      .section-title {
        font-size: 32px;
      }
    }