/* roulang page: index */
:root {
      --primary: #F04E30;
      --primary-light: #FF5A3C;
      --primary-soft: rgba(240, 78, 48, 0.1);
      --secondary: #0B1D3A;
      --secondary-light: #13294B;
      --accent: #FFB81C;
      --accent-soft: rgba(255, 184, 28, 0.18);
      --white: #FFFFFF;
      --bg-light: #FAFBFD;
      --gray-50: #f8fafc;
      --gray-100: #f1f5f9;
      --gray-200: #e2e8f0;
      --gray-300: #cbd5e1;
      --gray-600: #475569;
      --gray-700: #334155;
      --gray-800: #1e293b;
      --text-main: #1e293b;
      --text-soft: #475569;
      --border-light: #e2e8f0;
      --shadow-sm: 0 8px 30px rgba(0,0,0,0.04);
      --shadow-md: 0 16px 40px rgba(240,78,48,0.10);
      --shadow-hover: 0 20px 40px rgba(240,78,48,0.16);
      --radius-xl: 24px;
      --radius-lg: 20px;
      --radius-md: 16px;
      --radius-full: 50px;
      --radius-input: 14px;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
      --transition: 0.2s cubic-bezier(0.23, 1, 0.32, 1);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    img {
      max-width: 100%;
      display: block;
    }
    button, input, textarea {
      font-family: inherit;
    }
    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: rgba(11, 29, 58, 0.72);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-bottom: 1px solid rgba(255,255,255,0.08);
      transition: background 0.3s ease, box-shadow 0.3s;
    }
    .nav.scrolled {
      background: rgba(11, 29, 58, 0.9);
      box-shadow: 0 10px 25px -8px rgba(0,0,0,0.2);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    .logo {
      font-size: 1.9rem;
      font-weight: 750;
      color: white;
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo span {
      background: linear-gradient(135deg, #FF5A3C 0%, #FFB81C 90%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      color: rgba(255,255,255,0.82);
      font-weight: 500;
      font-size: 0.95rem;
      position: relative;
      padding: 6px 0;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: white;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2.5px;
      background: var(--primary-light);
      border-radius: 4px;
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .menu-toggle {
      display: none;
      background: transparent;
      border: none;
      color: var(--primary-light);
      font-size: 1.8rem;
      cursor: pointer;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: var(--secondary);
      backdrop-filter: blur(20px);
      flex-direction: column;
      padding: 28px 32px;
      gap: 20px;
      border-top: 1px solid rgba(255,255,255,0.1);
    }
    .mobile-menu a {
      color: white;
      font-size: 1.2rem;
      font-weight: 500;
      border-left: 4px solid var(--primary-light);
      padding-left: 18px;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #0B1D3A 0%, #1F2F4A 30%, #C84B31 100%);
      position: relative;
      overflow: hidden;
    }
    .hero-bg {
      position: absolute;
      inset: 0;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.3;
      mix-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 700px;
      color: white;
    }
    .hero h1 {
      font-size: clamp(2.6rem, 6vw, 4.2rem);
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 1.2rem;
    }
    .hero h1 span {
      background: linear-gradient(to right, #FFB81C, #FF5A3C);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.85);
      margin-bottom: 2.8rem;
      max-width: 550px;
    }
    .btn-group {
      display: flex;
      gap: 18px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      padding: 14px 34px;
      border-radius: var(--radius-full);
      font-weight: 600;
      transition: all 0.3s ease;
      text-align: center;
      font-size: 1rem;
    }
    .btn-primary {
      background: linear-gradient(135deg, #FF5A3C, #F04E30);
      color: white;
      border: none;
      box-shadow: 0 10px 20px -8px rgba(240,78,48,0.5);
    }
    .btn-primary:hover {
      background: linear-gradient(135deg, #FF6F4C, #FF4120);
      box-shadow: 0 18px 30px -6px rgba(240,78,48,0.45);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
    }
    .btn-outline:hover {
      background: rgba(255,255,255,0.12);
      border-color: #FFB81C;
      color: #FFB81C;
    }

    section {
      padding: 110px 0;
    }
    .section-title {
      font-size: 2.3rem;
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 18px;
      position: relative;
    }
    .section-sub {
      color: var(--gray-600);
      font-size: 1.1rem;
      max-width: 600px;
    }

    /* 优势卡片 */
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 30px;
      margin-top: 48px;
    }
    .advantage-card {
      background: white;
      border-radius: var(--radius-xl);
      padding: 36px 24px;
      box-shadow: var(--shadow-sm);
      transition: all 0.3s;
      position: relative;
      border: 1px solid var(--border-light);
    }
    .advantage-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(240,78,48,0.25);
    }
    .badge-num {
      position: absolute;
      top: 17px;
      right: 22px;
      background: var(--accent-soft);
      color: #b45319;
      font-weight: 700;
      font-size: 1.8rem;
      padding: 4px 14px;
      border-radius: 40px;
      background: #fff7e6;
    }
    .icon-circle {
      width: 60px;
      height: 60px;
      background: rgba(240,78,48,0.1);
      border-radius: 18px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 1.8rem;
      margin-bottom: 20px;
      color: var(--primary);
    }
    .card-title {
      font-weight: 700;
      font-size: 1.35rem;
      margin-bottom: 12px;
    }

    /* 核心服务 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 35px;
      margin-top: 48px;
    }
    .service-card {
      background: white;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: 0.25s;
    }
    .service-card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-6px);
    }
    .service-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }
    .service-body {
      padding: 28px 28px 35px;
    }

    /* 数据条 */
    .data-strip {
      background: linear-gradient(120deg, #0B1D3A, #1C3052);
      border-radius: 36px;
      margin-top: 32px;
      display: grid;
      grid-template-columns: repeat(4,1fr);
      padding: 40px 20px;
      text-align: center;
      color: white;
    }
    .data-item {
      font-weight: 800;
    }
    .data-num {
      font-size: 3.4rem;
      color: var(--accent);
      display: inline-block;
    }

    /* 解决方案交替 */
    .solution-row {
      display: flex;
      gap: 60px;
      align-items: center;
      margin-bottom: 70px;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-text {
      flex: 1;
    }
    .solution-img {
      flex: 1;
      border-radius: 28px;
      overflow: hidden;
    }

    /* 案例卡片 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 30px;
      margin-top: 38px;
    }
    .case-card {
      background: white;
      border-radius: var(--radius-xl);
      overflow: hidden;
    }
    .case-img {
      height: 200px;
      background-size: cover;
    }

    /* FAQ */
    .faq-list {
      margin-top: 32px;
      display: flex;
      flex-direction: column;
      gap: 18px;
    }
    .faq-item {
      background: white;
      border-radius: 18px;
      padding: 24px 30px;
      cursor: pointer;
      border:1px solid #edf2f7;
    }
    .faq-q {
      display: flex;
      justify-content: space-between;
      font-weight: 600;
    }
    .faq-a {
      max-height: 0;
      overflow: hidden;
      transition: 0.28s;
    }
    .faq-item.open .faq-a {
      max-height: 180px;
      margin-top: 16px;
    }

    /* CTA 表单 */
    .cta-section {
      background: linear-gradient(135deg, #162A45, #0f2239);
      border-radius: 48px;
      padding: 60px 50px;
    }
    .form-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr) auto;
      gap: 16px;
      margin-top: 28px;
    }
    .footer {
      background: #0B1D3A;
      color: #ccc;
      padding: 50px 0 28px;
    }
    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2,1fr); }
      .services-grid, .cases-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .mobile-menu.active { display: flex; }
      .grid-4, .services-grid, .cases-grid { grid-template-columns: 1fr; }
      .data-strip { grid-template-columns: repeat(2,1fr); }
      .solution-row { flex-direction: column; }
      .form-grid { grid-template-columns: 1fr; }
    }

.input-field{background:white;border-radius:14px;padding:14px;border:none;}.faq-item.open .faq-a{max-height:200px;}