/* roulang page: index */
:root {
      --primary: #E8380D;
      --primary-dark: #C92D0A;
      --secondary-dark: #1A1A2E;
      --accent-blue: #0F3460;
      --neon-cyan: #00E5FF;
      --light-bg: #F8F9FA;
      --white: #FFFFFF;
      --gray-100: #F4F5F7;
      --gray-200: #E2E4E9;
      --gray-600: #5A6072;
      --gray-800: #2A2F45;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-sm: 0 2px 16px rgba(0,0,0,0.04);
      --shadow-hover: 0 8px 32px rgba(232,56,13,0.12);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-mono: "Inter", "SF Pro Display", sans-serif;
      --transition: 0.25s ease-in-out;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: #FAFBFC;
      color: #1E1E24;
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-sans);
      font-weight: 700;
      margin: 0;
      color: var(--secondary-dark);
    }
    h1 {
      font-size: 56px;
      letter-spacing: -0.02em;
      line-height: 1.15;
    }
    h2 {
      font-size: 40px;
      line-height: 1.25;
    }
    h3 {
      font-size: 24px;
      font-weight: 600;
    }
    p, li {
      font-size: 16px;
      font-weight: 400;
      color: #4A4F5E;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航栏 SaaS 命令栏风格 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(26,26,46,0.88);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      z-index: 100;
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: 1300px;
      margin: 0 auto;
      padding: 0 28px;
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      font-size: 28px;
      background: linear-gradient(135deg, #E8380D, #FF6B3D);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      line-height: 1;
    }
    .logo-text {
      font-size: 22px;
      font-weight: 700;
      color: white;
      letter-spacing: 1px;
      background: linear-gradient(to right, #fff, #ddd);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
      margin: 0;
    }
    .nav-links a {
      color: #ddd;
      font-size: 14px;
      font-weight: 500;
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: 0.2s;
    }
    .nav-links a:hover {
      color: white;
      border-bottom-color: var(--primary);
    }
    .nav-right {
      display: flex;
      align-items: center;
      gap: 16px;
    }
    .search-box {
      position: relative;
    }
    .search-input {
      background: rgba(255,255,255,0.1);
      border: 1px solid rgba(255,255,255,0.2);
      border-radius: 40px;
      padding: 10px 18px;
      width: 160px;
      font-size: 14px;
      color: white;
      outline: none;
      transition: width 0.3s ease, border-color 0.2s;
      backdrop-filter: blur(10px);
    }
    .search-input::placeholder {
      color: #aaa;
    }
    .search-input:focus {
      width: 240px;
      border-color: var(--neon-cyan);
      box-shadow: 0 0 10px rgba(0,229,255,0.3);
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      border: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: 0.2s;
      cursor: pointer;
      font-size: 14px;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 0 14px rgba(232,56,13,0.5);
      color: white;
    }
    .mobile-menu-icon {
      display: none;
      color: white;
      font-size: 24px;
      cursor: pointer;
    }
    /* Hero */
    #hero {
      height: 100vh;
      background: radial-gradient(circle at 30% 40%, #1A1A2E, #0A0A14);
      display: flex;
      align-items: center;
      position: relative;
      padding-top: 72px;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .hero-text {
      flex: 1;
      color: white;
    }
    .hero-text h1 {
      color: white;
      font-size: 64px;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 18px;
      color: #ccc;
      margin-bottom: 36px;
      max-width: 480px;
    }
    .btn-ghost {
      background: transparent;
      border: 1px solid white;
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 500;
      margin-left: 16px;
      transition: 0.2s;
    }
    .btn-ghost:hover {
      background: white;
      color: var(--primary);
    }
    .hero-visual {
      flex: 1;
      display: flex;
      justify-content: center;
    }
    .hero-visual img {
      max-height: 480px;
      filter: drop-shadow(0 20px 35px rgba(232,56,13,0.3));
      animation: float 4s ease-in-out infinite;
    }
    @keyframes float {
      0% { transform: translateY(0px); }
      50% { transform: translateY(-12px); }
      100% { transform: translateY(0px); }
    }
    /* 通用板块 */
    section {
      padding: 100px 0;
    }
    .section-title {
      margin-bottom: 48px;
    }
    .section-title h2 {
      margin-bottom: 12px;
    }
    /* 优势卡片不对称 */
    .features-grid {
      display: flex;
      gap: 28px;
      align-items: flex-start;
    }
    .feature-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--shadow-sm);
      border: 1px solid rgba(0,0,0,0.04);
      transition: all 0.3s;
      flex: 1;
    }
    .feature-card.wide {
      flex: 1.3;
    }
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(232,56,13,0.2);
    }
    .feature-icon {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 16px;
    }
    .feature-number {
      font-size: 42px;
      font-weight: 800;
      color: var(--secondary-dark);
      font-family: var(--font-mono);
    }
    /* 服务体系左右交替 */
    .service-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
    }
    .service-img img {
      border-radius: 16px;
      box-shadow: 0 15px 30px rgba(0,0,0,0.08);
    }
    /* 数据条带 */
    .stats-strip {
      background: #1A1A2E;
      padding: 60px 0;
      display: flex;
      justify-content: space-around;
      text-align: center;
    }
    .stat-item h3 {
      font-size: 48px;
      color: var(--neon-cyan);
      font-weight: 800;
    }
    /* 案例网格 2x2 */
    .cases-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .case-card {
      position: relative;
      border-radius: 12px;
      overflow: hidden;
      aspect-ratio: 16/10;
    }
    .case-card img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .case-info {
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      background: linear-gradient(transparent, rgba(0,0,0,0.7));
      color: white;
      padding: 24px;
    }
    /* FAQ */
    .faq-layout {
      display: flex;
      gap: 40px;
    }
    .faq-categories {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }
    .faq-cat {
      padding: 10px 18px;
      border-radius: 20px;
      cursor: pointer;
      font-weight: 500;
    }
    .faq-cat.active {
      background: var(--primary);
      color: white;
    }
    .accordion-item {
      border-bottom: 1px solid #eee;
      padding: 16px 0;
    }
    /* CTA */
    .cta-block {
      background: linear-gradient(135deg, #E8380D, #B52D0A);
      border-radius: 24px;
      padding: 64px;
      text-align: center;
      color: white;
    }
    .footer {
      background: #1A1A2E;
      color: #ccc;
      padding: 60px 0 20px;
    }
    @media (max-width: 1024px) {
      h1 { font-size: 44px; }
      .hero-grid { flex-direction: column; text-align: center; }
    }
    @media (max-width: 768px) {
      .nav-links, .search-box { display: none; }
      .mobile-menu-icon { display: block; }
      .features-grid, .service-row, .faq-layout { flex-direction: column; }
      .cases-grid { grid-template-columns: 1fr; }
      h2 { font-size: 32px; }
    }