/* roulang page: index */
:root {
      --primary: #2E3A8C;
      --primary-dark: #1E2670;
      --primary-light: #4B5CC4;
      --accent: #F5B642;
      --accent-light: #FADB7F;
      --bg: #F5F6FA;
      --card-bg: #FFFFFF;
      --dark-bg: #1A1F3A;
      --footer-bg: #0F1324;
      --text-main: #1F2329;
      --text-muted: #86909C;
      --text-on-dark: #FFFFFF;
      --text-on-dark-muted: #B0B8D1;
      --green: #00B578;
      --orange: #FF9F0A;
      --red: #FA5151;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.04), 0 0 1px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 24px rgba(0,0,0,0.08), 0 0 1px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-pill: 40px;
      --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
    }

    * { box-sizing: border-box; margin: 0; padding: 0; }
    html { scroll-behavior: smooth; }
    body {
      font-family: var(--font-sans);
      background: var(--bg);
      color: var(--text-main);
      line-height: 1.6;
      font-size: 16px;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0; left: 0; right: 0;
      background: #fff;
      height: 72px;
      display: flex;
      align-items: center;
      z-index: 1000;
      box-shadow: 0 1px 8px rgba(0,0,0,0.06);
      transition: box-shadow 200ms;
    }
    .header .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      text-decoration: none;
    }
    .logo i { font-style: normal; font-size: 26px; color: var(--accent); }
    .nav-links {
      display: flex;
      gap: 32px;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-main);
      font-size: 15px;
      font-weight: 500;
      position: relative;
      padding-bottom: 6px;
      transition: color 200ms;
    }
    .nav-links a:hover { color: var(--primary); }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0; left: 0;
      width: 0; height: 2px;
      background: var(--accent);
      transition: width 200ms;
    }
    .nav-links a:hover::after { width: 100%; }
    .btn-primary {
      background: var(--primary);
      color: #fff;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      display: inline-block;
      transition: all 200ms;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      text-decoration: none;
      display: inline-block;
      transition: all 200ms;
    }
    .btn-outline:hover {
      background: rgba(46,58,140,0.08);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
    }
    .hamburger span {
      width: 24px; height: 2px;
      background: var(--text-main);
      border-radius: 2px;
      transition: 0.3s;
    }
    .mobile-menu {
      position: fixed; top: 0; right: -100%;
      width: 280px; height: 100vh;
      background: #fff;
      z-index: 2000;
      padding: 40px 24px;
      display: flex;
      flex-direction: column;
      gap: 24px;
      transition: right 0.3s ease;
      box-shadow: -4px 0 20px rgba(0,0,0,0.1);
    }
    .mobile-menu.active { right: 0; }
    .mobile-close {
      align-self: flex-end;
      font-size: 28px;
      cursor: pointer;
      border: none;
      background: transparent;
      color: var(--text-main);
    }
    .overlay {
      position: fixed; inset: 0;
      background: rgba(0,0,0,0.5);
      z-index: 1500;
      display: none;
    }
    .overlay.active { display: block; }

    /* Hero */
    .hero {
      padding: 140px 0 80px;
      background: linear-gradient(135deg, #F5F6FA 0%, #eef0f8 100%);
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-text { flex: 1; }
    .hero-text h1 {
      font-size: 40px; font-weight: 700; line-height: 1.3;
      color: var(--text-main); margin-bottom: 16px;
    }
    .hero-text .sub {
      font-size: 16px; color: var(--text-muted); margin-bottom: 28px;
      line-height: 1.8;
    }
    .hero-buttons { display: flex; gap: 16px; margin-bottom: 32px; }
    .micro-stats {
      display: flex; gap: 24px;
      font-size: 12px; color: var(--text-muted);
    }
    .micro-stats span { color: var(--accent); font-weight: 700; }
    .hero-visual {
      flex: 1;
      background: #1A1F3A;
      border-radius: var(--radius-card);
      padding: 40px;
      display: flex;
      justify-content: center;
      align-items: center;
      position: relative;
      overflow: hidden;
      min-height: 360px;
    }
    .star-canvas {
      width: 100%; height: 100%;
      position: relative;
    }
    .star { position: absolute; background: white; border-radius: 50%; opacity: 0.7; }
    .orbit { position: absolute; border: 1px solid rgba(245,182,66,0.2); border-radius: 50%; }

    /* 通用板块 */
    section { padding: 80px 0; }
    .section-title {
      font-size: 32px; font-weight: 600; text-align: center;
      margin-bottom: 16px; color: var(--text-main);
    }
    .section-sub {
      text-align: center; color: var(--text-muted);
      margin-bottom: 48px; font-size: 16px;
    }

    /* 卡片网格 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: all 250ms ease-out;
    }
    .card:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-4px);
    }
    .icon-circle {
      width: 56px; height: 56px;
      background: rgba(46,58,140,0.08);
      border-radius: 50%;
      display: flex; align-items: center; justify-content: center;
      margin-bottom: 20px;
      font-size: 24px; color: var(--primary);
    }
    .card h3 { font-size: 20px; margin-bottom: 12px; }
    .card p { font-size: 14px; color: var(--text-muted); line-height: 1.7; }
    .card .link {
      margin-top: 16px; color: var(--accent);
      font-weight: 600; font-size: 14px;
      text-decoration: none; display: inline-block;
      transition: transform 200ms;
    }
    .card .link:hover { transform: translateX(4px); }

    /* 深色数据区 */
    .dark-section {
      background: var(--dark-bg);
      color: var(--text-on-dark);
    }
    .dark-section .section-title { color: white; }
    .stat-number {
      font-size: 48px; font-weight: 700;
      background: linear-gradient(135deg, #F5B642, #FADB7F);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .stat-label { font-size: 14px; color: var(--text-on-dark-muted); }

    /* 案例卡片 */
    .case-img {
      aspect-ratio: 16/9;
      background: #e9ebf0;
      border-radius: var(--radius-card) var(--radius-card) 0 0;
      position: relative;
      overflow: hidden;
      display: flex; align-items: center; justify-content: center;
    }
    .case-img img { width: 100%; height: 100%; object-fit: cover; }
    .case-overlay {
      position: absolute; inset: 0;
      background: rgba(46,58,140,0.7);
      display: flex; align-items: center; justify-content: center;
      opacity: 0; transition: 250ms;
      color: white; font-weight: 600;
    }
    .case-card:hover .case-overlay { opacity: 1; }
    .case-card { background: white; border-radius: var(--radius-card); box-shadow: var(--shadow-sm); overflow: hidden; }
    .case-body { padding: 24px; }
    .tag {
      background: #f0f1f5; color: var(--text-main);
      padding: 4px 12px; border-radius: 20px;
      font-size: 12px; font-weight: 500;
    }

    /* 时间轴 */
    .timeline { position: relative; padding-left: 40px; }
    .timeline::before {
      content: ''; position: absolute; left: 16px; top: 0; bottom: 0;
      width: 2px; background: rgba(46,58,140,0.2);
    }
    .step { position: relative; margin-bottom: 32px; }
    .step-num {
      position: absolute; left: -40px; top: 0;
      width: 40px; height: 40px; background: var(--primary);
      color: white; border-radius: 50%; display: flex;
      align-items: center; justify-content: center;
      font-weight: 700; font-size: 18px;
    }

    /* FAQ */
    .faq-container { max-width: 800px; margin: 0 auto; }
    .faq-item { border-bottom: 1px solid #e5e7eb; }
    .faq-question {
      padding: 20px 0; cursor: pointer; display: flex;
      justify-content: space-between; align-items: center;
      font-weight: 600; font-size: 16px;
    }
    .faq-answer {
      max-height: 0; overflow: hidden;
      transition: max-height 0.3s ease;
      font-size: 14px; color: var(--text-muted);
      padding-bottom: 0;
    }
    .faq-item.active .faq-answer { max-height: 200px; padding-bottom: 16px; }
    .faq-item.active .faq-question { color: var(--primary); }

    /* CTA横幅 */
    .cta-banner {
      background: linear-gradient(135deg, #2E3A8C, #4B5CC4);
      padding: 80px 0; text-align: center;
      color: white; border-radius: 20px;
      margin: 0 24px;
    }
    .btn-pill {
      background: white; color: var(--primary);
      padding: 14px 36px; border-radius: var(--radius-pill);
      font-weight: 700; text-decoration: none;
      display: inline-block; margin-top: 24px;
      transition: all 200ms;
    }
    .btn-pill:hover { box-shadow: 0 4px 15px rgba(0,0,0,0.15); }

    /* 表单 */
    .contact-form {
      max-width: 600px; margin: 60px auto 0;
    }
    .form-input {
      width: 100%; padding: 14px; border-radius: 8px;
      border: 1px solid #d1d5db; background: #F5F6FA;
      margin-bottom: 16px; font-size: 16px;
      transition: 0.2s;
    }
    .form-input:focus {
      outline: none; border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(46,58,140,0.2);
    }

    /* 页脚 */
    .footer {
      background: var(--footer-bg);
      color: white; padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid; grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a { color: var(--text-on-dark-muted); text-decoration: none; font-size: 14px; }
    .copyright {
      margin-top: 40px; padding-top: 20px;
      border-top: 1px solid rgba(255,255,255,0.1);
      text-align: center; font-size: 14px;
      color: var(--text-on-dark-muted);
    }

    @media (max-width: 1023px) {
      .grid-3 { grid-template-columns: repeat(2, 1fr); }
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .hero .container { flex-direction: column; }
      .hero-visual { width: 100%; min-height: 280px; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .grid-3, .grid-4 { grid-template-columns: 1fr; }
      .section-title { font-size: 24px; }
      .hero-text h1 { font-size: 28px; }
      .hero-buttons { flex-direction: column; }
      .timeline { padding-left: 32px; }
      .hero { padding: 100px 0 60px; }
      .header { height: 60px; }
      .card { padding: 24px; }
      .cta-banner { margin: 0 16px; padding: 48px 16px; }
    }