/* roulang page: index */
:root {
      --primary-deep: #1B3A5C;
      --primary-hover: #0F2440;
      --accent-cyan: #00A3A3;
      --accent-hover: #008080;
      --bg-page: #F8FAFC;
      --bg-card: #FFFFFF;
      --bg-subtle: #F1F5F9;
      --text-heading: #0F172A;
      --text-title: #1B3A5C;
      --text-card-title: #1E293B;
      --text-body: #475569;
      --text-muted: #94A3B8;
      --border-light: #E2E8F0;
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04), 0 1px 3px rgba(0,0,0,0.02);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.06);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 8px;
      --radius-container: 16px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "WenQuanYi Micro Hei", sans-serif;
      --font-number: "Inter", "SF Pro Text", sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-page);
      color: var(--text-body);
      line-height: 1.8;
      -webkit-font-smoothing: antialiased;
    }

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

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: all 0.2s ease;
      border: none;
      outline: none;
    }

    input, textarea {
      font-family: inherit;
      transition: border 0.2s ease, box-shadow 0.2s ease;
    }

    /* 导航 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(8px);
      border-bottom: 1px solid var(--border-light);
      z-index: 1000;
      transition: box-shadow 0.2s ease;
    }
    .main-header.scrolled {
      box-shadow: var(--shadow-card);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--primary-deep);
      letter-spacing: 1px;
    }
    .logo i {
      color: var(--accent-cyan);
      margin-right: 4px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-size: 1rem;
      font-weight: 500;
      color: var(--text-body);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary-deep);
      border-bottom-color: var(--primary-deep);
    }
    .nav-cta {
      background: var(--accent-cyan);
      color: white !important;
      padding: 10px 24px !important;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none !important;
      box-shadow: 0 2px 8px rgba(0,163,163,0.3);
    }
    .nav-cta:hover {
      background: var(--accent-hover);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: var(--primary-deep);
      background: none;
      border: none;
    }
    .mobile-drawer {
      position: fixed;
      top: 0;
      right: -100%;
      width: 280px;
      height: 100vh;
      background: white;
      box-shadow: -5px 0 20px rgba(0,0,0,0.1);
      z-index: 1001;
      transition: right 0.3s ease;
      padding: 24px;
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .mobile-drawer.open {
      right: 0;
    }
    .drawer-overlay {
      position: fixed;
      inset: 0;
      background: rgba(0,0,0,0.4);
      z-index: 1000;
      display: none;
    }
    .drawer-overlay.show {
      display: block;
    }

    /* Hero */
    .hero {
      padding: 140px 0 100px;
      background-color: var(--bg-page);
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
    }
    .hero h1 {
      font-size: clamp(2rem, 5vw, 3.2rem);
      font-weight: 800;
      color: var(--text-heading);
      line-height: 1.3;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-body);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--primary-deep);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
    }
    .btn-primary:hover {
      background: var(--primary-hover);
    }
    .btn-outline {
      background: transparent;
      color: var(--primary-deep);
      border: 2px solid var(--primary-deep);
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }
    .btn-outline:hover {
      background: #E2E8F0;
    }
    .hero-image {
      flex: 1;
      position: relative;
    }
    .hero-image img {
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      width: 100%;
    }

    /* 通用板块 */
    .section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 2.2rem;
      font-weight: 600;
      color: var(--text-title);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      text-align: center;
      color: var(--text-muted);
      max-width: 680px;
      margin: 0 auto 48px;
    }

    /* 痛点 */
    .pain-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .pain-card {
      background: var(--bg-subtle);
      border-left: 4px solid var(--primary-deep);
      padding: 32px;
      border-radius: 0 var(--radius-card) var(--radius-card) 0;
    }
    .pain-icon {
      font-size: 2rem;
      color: var(--accent-cyan);
      margin-bottom: 12px;
    }

    /* 解决方案分层 */
    .solution-block {
      display: flex;
      gap: 48px;
      align-items: center;
      margin-bottom: 80px;
    }
    .solution-block.reverse {
      flex-direction: row-reverse;
    }
    .solution-text {
      flex: 1;
    }
    .solution-img {
      flex: 1;
    }
    .solution-img img {
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }
    .learn-more {
      color: var(--primary-deep);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
      margin-top: 12px;
    }
    .learn-more i {
      font-size: 0.9rem;
    }

    /* 数据卡片 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      text-align: center;
    }
    .stat-card {
      background: var(--bg-card);
      padding: 40px 20px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: box-shadow 0.2s;
    }
    .stat-card:hover {
      box-shadow: var(--shadow-hover);
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent-cyan);
      font-family: var(--font-number);
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }
    .testimonial-card {
      background: var(--bg-card);
      padding: 32px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      border-left: 3px solid var(--accent-cyan);
    }
    .testimonial-text {
      font-style: italic;
      margin-bottom: 16px;
    }
    .client-name {
      font-weight: 600;
      color: var(--text-heading);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      color: var(--primary-deep);
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      font-size: 1.1rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      background: var(--bg-page);
      padding: 0 16px;
      margin-top: 8px;
      border-radius: 8px;
    }
    .faq-answer.open {
      max-height: 200px;
      padding: 16px;
    }

    /* CTA */
    .cta-section {
      background: var(--primary-deep);
      color: white;
      padding: 80px 0;
      text-align: center;
    }
    .cta-form {
      display: flex;
      flex-wrap: wrap;
      gap: 16px;
      justify-content: center;
      margin-top: 32px;
    }
    .cta-form input {
      padding: 14px 20px;
      border-radius: var(--radius-input);
      border: none;
      background: white;
      min-width: 200px;
      color: var(--text-heading);
    }
    .cta-form input:focus {
      outline: 2px solid var(--accent-cyan);
    }
    .btn-submit {
      background: var(--accent-cyan);
      color: white;
      padding: 14px 40px;
      border-radius: var(--radius-btn);
      font-weight: 600;
    }

    /* 页脚 */
    .footer {
      background: #0F172A;
      color: #CBD5E1;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a {
      color: #CBD5E1;
    }
    .footer-bottom {
      border-top: 1px solid #334155;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 0.9rem;
    }

    @media (max-width: 1024px) {
      .hero .container { flex-direction: column; }
      .stats-grid { grid-template-columns: 1fr 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .pain-grid, .testimonial-grid, .stats-grid { grid-template-columns: 1fr; }
      .solution-block, .solution-block.reverse { flex-direction: column; }
    }