/* roulang page: index */
:root {
      --primary: #E43D2A;
      --primary-strong: #C8321F;
      --primary-soft: rgba(228,61,42,0.08);
      --accent: #00E5A0;
      --dark-bg: #1A1D29;
      --dark-surface: #2A2F3C;
      --text-heading: #1A1D29;
      --text-body: #4A4F5C;
      --text-muted: #8A8F9C;
      --paper: #F5F0EB;
      --white: #FFFFFF;
      --border-light: #E8E5E1;
      --border-input: #D1CDE6;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --radius-xl: 20px;
      --shadow-card: 0 4px 20px rgba(26,29,41,0.06);
      --shadow-card-hover: 0 8px 30px rgba(228,61,42,0.12);
      --font-heading: 'AlibabaPuHuiTiB', 'PingFang SC', 'Microsoft YaHei', '黑体', system-ui, -apple-system, sans-serif;
      --font-body: 'Source Han Sans SC', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --font-mono: 'SF Mono', 'Cascadia Code', 'Consolas', 'Menlo', monospace;
      --spacing-section: 100px;
      --max-width: 1280px;
      --nav-height: 72px;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
      -webkit-text-size-adjust: 100%;
    }
    body {
      font-family: var(--font-body);
      font-size: 16px;
      line-height: 1.6;
      color: var(--text-body);
      background-color: var(--white);
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    button, input, textarea, select {
      font-family: inherit;
      font-size: inherit;
      outline: none;
    }
    .container {
      width: 100%;
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: 40px;
      padding-right: 40px;
    }
    h1, h2, h3, .h1, .h2, .h3 {
      font-family: var(--font-heading);
      font-weight: 700;
      color: var(--text-heading);
      letter-spacing: -0.02em;
    }
    h1 { font-size: 48px; line-height: 1.2; }
    h2 { font-size: 36px; line-height: 1.3; }
    h3 { font-size: 22px; line-height: 1.4; }
    .caption {
      font-size: 13px;
      color: var(--text-muted);
    }
    .section {
      padding-top: var(--spacing-section);
      padding-bottom: var(--spacing-section);
    }
    /* 按钮组件 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      padding: 14px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 16px;
      transition: all 0.2s ease;
      cursor: pointer;
      border: 2px solid transparent;
      white-space: nowrap;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border-color: var(--primary);
    }
    .btn-primary:hover {
      background: var(--primary-strong);
      border-color: var(--primary-strong);
      transform: translateY(-1px);
      box-shadow: 0 8px 18px rgba(228,61,42,0.25);
    }
    .btn-outline {
      background: transparent;
      color: var(--primary);
      border-color: var(--primary);
    }
    .btn-outline:hover {
      background: var(--primary-soft);
      border-color: var(--primary);
    }
    .btn-light {
      background: white;
      color: var(--dark-bg);
      border-color: white;
    }
    .btn-light:hover {
      background: #f0f0f0;
      border-color: #f0f0f0;
    }
    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: rgba(26,29,41,0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 100;
      display: flex;
      align-items: center;
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-family: var(--font-heading);
      font-weight: 900;
      font-size: 24px;
      color: white;
      letter-spacing: -0.01em;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      color: var(--primary);
    }
    .desktop-nav {
      display: flex;
      align-items: center;
      gap: 36px;
    }
    .desktop-nav a {
      color: rgba(255,255,255,0.85);
      font-weight: 500;
      font-size: 15px;
      transition: color 0.2s;
    }
    .desktop-nav a:hover {
      color: white;
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      z-index: 110;
    }
    .hamburger span {
      width: 26px;
      height: 2px;
      background: white;
      border-radius: 2px;
      transition: 0.3s;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      right: 0;
      width: 75%;
      max-width: 320px;
      height: 100vh;
      background: var(--dark-bg);
      z-index: 105;
      padding: 100px 32px 40px;
      flex-direction: column;
      gap: 32px;
      box-shadow: -10px 0 30px rgba(0,0,0,0.3);
    }
    .mobile-menu a {
      color: white;
      font-size: 20px;
      font-weight: 500;
    }
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      background: rgba(26,29,41,0.95);
      backdrop-filter: blur(20px);
      border-top: 1px solid rgba(255,255,255,0.1);
      z-index: 90;
      justify-content: space-around;
      padding: 8px 16px 12px;
    }
    .mobile-bottom-nav a {
      color: rgba(255,255,255,0.7);
      font-size: 11px;
      font-weight: 500;
      display: flex;
      flex-direction: column;
      align-items: center;
      gap: 4px;
    }
    /* Hero */
    #hero {
      min-height: 100vh;
      background: linear-gradient(135deg, #1A1D29 0%, #2A2F3C 100%);
      display: flex;
      align-items: center;
      padding-top: var(--nav-height);
      position: relative;
      overflow: hidden;
    }
    #hero::after {
      content: "";
      position: absolute;
      right: 0;
      bottom: 0;
      width: 700px;
      height: 500px;
      background: url('/assets/images/backpic/back-1.webp') no-repeat center/contain;
      opacity: 0.18;
      pointer-events: none;
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
      position: relative;
      z-index: 2;
    }
    .hero-left h1 {
      color: white;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 18px;
      color: rgba(255,255,255,0.7);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .metric-board {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .metric-card {
      background: rgba(255,255,255,0.06);
      backdrop-filter: blur(8px);
      border-radius: var(--radius-lg);
      padding: 24px 28px;
      border: 1px solid rgba(255,255,255,0.08);
      color: white;
    }
    .metric-value {
      font-family: var(--font-mono);
      font-size: 38px;
      font-weight: 700;
      color: var(--accent);
      letter-spacing: -0.5px;
    }
    .metric-label {
      font-size: 14px;
      color: rgba(255,255,255,0.65);
      margin-top: 6px;
    }
    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr;
      gap: 28px;
    }
    .service-main-card {
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 40px;
      box-shadow: var(--shadow-card);
      display: flex;
      flex-direction: column;
      justify-content: center;
    }
    .service-tag {
      display: inline-block;
      background: var(--primary-soft);
      color: var(--primary);
      font-weight: 600;
      font-size: 13px;
      padding: 4px 12px;
      border-radius: 20px;
      margin-bottom: 20px;
    }
    .service-stack {
      display: flex;
      flex-direction: column;
      gap: 20px;
    }
    .service-card {
      background: var(--white);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-card);
      transition: all 0.25s;
    }
    .service-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-2px);
    }
    /* 对比 */
    .benchmark-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: start;
    }
    .bench-col h3 {
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .bench-item {
      display: flex;
      gap: 16px;
      margin-bottom: 28px;
    }
    .bench-icon {
      font-size: 22px;
      width: 32px;
      text-align: center;
    }
    .highlight-bar {
      background: var(--dark-bg);
      border-radius: var(--radius-lg);
      padding: 32px 40px;
      margin-top: 48px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
      gap: 24px;
    }
    .highlight-number {
      font-family: var(--font-mono);
      font-size: 44px;
      font-weight: 700;
      color: var(--accent);
    }
    /* FAQ */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .faq-item {
      border: 1px solid var(--border-light);
      border-radius: var(--radius-sm);
      background: white;
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 22px 24px;
      font-size: 18px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text-heading);
    }
    .faq-answer {
      padding: 0 24px 22px;
      display: none;
      color: var(--text-body);
    }
    .faq-item.open .faq-answer {
      display: block;
    }
    /* 表单 */
    .contact-grid {
      display: grid;
      grid-template-columns: 1fr 1.3fr;
      gap: 60px;
      align-items: center;
    }
    .input-field {
      width: 100%;
      padding: 14px 16px;
      border: 1px solid var(--border-input);
      border-radius: 6px;
      margin-bottom: 16px;
      transition: 0.2s;
    }
    .input-field:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(228,61,42,0.1);
    }
    .trust-badges {
      display: flex;
      gap: 24px;
      margin-top: 20px;
      color: var(--text-muted);
      font-size: 13px;
    }
    /* 页脚 */
    .footer {
      background: var(--dark-bg);
      color: var(--text-muted);
      padding: 60px 0 40px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }
    @media (max-width: 1024px) {
      .container { padding-left: 24px; padding-right: 24px; }
      h1 { font-size: 40px; }
      h2 { font-size: 30px; }
    }
    @media (max-width: 768px) {
      .desktop-nav { display: none; }
      .hamburger { display: flex; }
      .mobile-bottom-nav { display: flex; }
      .hero-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      .benchmark-row { grid-template-columns: 1fr; gap: 40px; }
      .contact-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
    }