/* roulang page: index */
:root {
      --primary-red: #E63946;
      --deep-charcoal: #1D1D1D;
      --data-cyan: #00B4D8;
      --amber-yellow: #F4A261;
      --amber-hover: #F6B83D;
      --warm-gray: #F8F9FA;
      --gray-400: #6C757D;
      --gray-500: #495057;
      --gray-200: #E9ECEF;
      --gray-700: #343A40;
      --text-light: #ADB5BD;
      --white: #FFFFFF;
      --card-radius: 12px;
      --btn-radius: 6px;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.14);
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, sans-serif;
      --font-mono: 'DIN Alternate', 'Roboto Mono', 'Courier New', monospace;
      --container-max: 1200px;
      --section-padding: 80px 24px;
      --section-padding-mobile: 48px 16px;
    }

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

    body {
      font-family: var(--font-title);
      background-color: var(--warm-gray);
      color: var(--deep-charcoal);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

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

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s ease;
    }

    button, input {
      font-family: inherit;
      font-size: inherit;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 导航 */
    #main-nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--white);
      z-index: 1000;
      box-shadow: 0 2px 12px rgba(0,0,0,0.08);
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 32px;
      height: 72px;
      transition: box-shadow 0.3s;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--primary-red);
      letter-spacing: -0.5px;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 2rem;
    }

    .nav-links a {
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--deep-charcoal);
      position: relative;
      padding: 0.25rem 0;
    }

    .nav-links a.active {
      color: var(--primary-red);
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--primary-red);
      transition: width 0.2s;
    }

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

    .nav-cta {
      background: var(--amber-yellow);
      color: var(--deep-charcoal);
      font-weight: 600;
      padding: 10px 24px;
      border-radius: var(--btn-radius);
      transition: background 0.2s, box-shadow 0.2s;
    }

    .nav-cta:hover {
      background: var(--amber-hover);
      box-shadow: 0 4px 12px rgba(244,162,97,0.4);
      color: var(--deep-charcoal);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: none;
      border: none;
      cursor: pointer;
    }
    .hamburger span {
      display: block;
      width: 28px;
      height: 3px;
      background: var(--primary-red);
      border-radius: 2px;
      transition: 0.2s;
    }

    /* 移动导航 */
    .mobile-menu {
      position: fixed;
      top: 0;
      right: -100%;
      width: 75%;
      max-width: 320px;
      height: 100vh;
      background: var(--white);
      box-shadow: -5px 0 25px rgba(0,0,0,0.15);
      z-index: 1100;
      padding: 2rem;
      display: flex;
      flex-direction: column;
      gap: 2rem;
      transition: right 0.3s ease;
    }
    .mobile-menu.open {
      right: 0;
    }
    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 500;
      color: var(--deep-charcoal);
    }

    /* 首屏 */
    #hero {
      position: relative;
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      background-blend-mode: overlay;
      background-color: rgba(29,29,29,0.65);
      margin-top: 72px;
    }
    .hero-content {
      color: var(--white);
      max-width: 700px;
      padding: 2rem 0;
    }
    .hero-content h1 {
      font-size: clamp(2.2rem, 6vw, 3rem);
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 2rem;
      line-height: 1.6;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--amber-yellow);
      color: var(--deep-charcoal);
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      display: inline-block;
      transition: background 0.2s, box-shadow 0.2s;
    }
    .btn-primary:hover {
      background: var(--amber-hover);
      box-shadow: 0 4px 14px rgba(244,162,97,0.45);
    }
    .btn-outline {
      border: 2px solid var(--primary-red);
      color: var(--white);
      padding: 14px 32px;
      border-radius: var(--btn-radius);
      font-weight: 600;
      background: transparent;
      transition: 0.2s;
    }
    .btn-outline:hover {
      background: var(--primary-red);
      color: var(--white);
    }

    /* 通用 section */
    section {
      padding: var(--section-padding);
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      margin-bottom: 1rem;
      color: var(--deep-charcoal);
    }

    /* 数据看板 */
    #dashboard {
      background: var(--deep-charcoal);
    }
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: rgba(255,255,255,0.05);
      border: 1px solid rgba(255,255,255,0.08);
      border-radius: 8px;
      padding: 24px 16px;
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-mono);
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--data-cyan);
      margin-bottom: 0.5rem;
    }
    .stat-label {
      color: var(--text-light);
      font-size: 0.9rem;
    }

    /* 服务矩阵 */
    #services .services-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--white);
      border-radius: var(--card-radius);
      padding: 24px;
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s, box-shadow 0.2s;
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .service-img {
      width: 100%;
      height: 140px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 1rem;
    }
    .service-card h3 {
      font-size: 1.3rem;
      margin-bottom: 0.5rem;
    }
    .service-desc {
      color: var(--gray-400);
      font-size: 0.9rem;
      margin-bottom: 1rem;
    }
    .tags {
      display: flex;
      flex-wrap: wrap;
      gap: 6px;
    }
    .tag {
      border: 1px solid var(--primary-red);
      color: var(--primary-red);
      font-size: 0.7rem;
      padding: 2px 10px;
      border-radius: 20px;
    }

    /* 对比 */
    #comparison .compare-container {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .compare-left, .compare-right {
      padding: 2rem;
      border-radius: var(--card-radius);
    }
    .compare-left {
      background: rgba(230,57,70,0.08);
    }
    .compare-right {
      background: rgba(0,180,216,0.08);
    }
    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      margin: 1.2rem 0;
      font-weight: 500;
    }

    /* FAQ */
    #faq .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      background: var(--white);
      border-radius: 12px;
      margin-bottom: 16px;
      padding: 1.2rem;
      cursor: pointer;
    }
    .faq-question {
      display: flex;
      align-items: center;
      gap: 12px;
      font-weight: 600;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--gray-500);
      padding-left: 2.5rem;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      margin-top: 1rem;
    }

    /* 表单 */
    #contact {
      background: url('/assets/images/backpic/back-2.webp') center/cover no-repeat;
      background-color: rgba(29,29,29,0.8);
      background-blend-mode: overlay;
    }
    .form-row {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
      align-items: center;
    }
    .form-row input {
      flex: 1;
      padding: 14px;
      border-radius: var(--btn-radius);
      border: 1px solid var(--gray-200);
      background: white;
    }
    .form-submit {
      background: var(--amber-yellow);
      border: none;
      padding: 14px 28px;
      font-weight: 600;
      border-radius: var(--btn-radius);
    }

    footer {
      background: var(--deep-charcoal);
      color: var(--text-light);
      padding: 48px 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    @media (max-width: 1024px) {
      .dashboard-grid { grid-template-columns: repeat(3,1fr); }
      .services-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .dashboard-grid { grid-template-columns: repeat(2,1fr); }
      .compare-container { grid-template-columns: 1fr; }
      .form-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      section { padding: var(--section-padding-mobile); }
    }
    @media (max-width: 480px) {
      .services-grid, .dashboard-grid { grid-template-columns: 1fr; }
    }