/* roulang page: index */
:root {
      --primary-red: #E12B38;
      --secondary-gray: #2C303A;
      --bg-warm: #F7F5F2;
      --text-dark: #1A1D23;
      --accent-orange: #FF6B35;
      --white: #FFFFFF;
      --light-gray: #F0EDE8;
      --card-bg: #FAF9F7;
      --border-light: #E5E2DD;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.1);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-img: 16px;
      --font-heading: "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-body: "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-number: "Inter", "Roboto", sans-serif;
      --transition: 0.3s ease;
      --max-width: 1200px;
      --section-padding: 100px 0;
      --mobile-padding: 60px 0;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-warm);
      color: var(--text-dark);
      line-height: 1.75;
      font-size: 16px;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }

    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 700;
      margin-top: 0;
    }

    a {
      color: inherit;
      text-decoration: none;
    }
    a:hover {
      color: var(--primary-red);
    }

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

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      transition: background 0.3s, box-shadow 0.3s;
      border-bottom: 1px solid transparent;
    }
    .site-header.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 1px 8px rgba(0,0,0,0.08);
      border-bottom: 1px solid var(--border-light);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-family: var(--font-heading);
      font-weight: 700;
      font-size: 1.8rem;
      color: var(--primary-red);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
    }
    .logo i {
      margin-right: 8px;
      font-size: 2rem;
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 2rem;
    }
    .nav-menu a {
      font-weight: 500;
      font-size: 1rem;
      color: var(--text-dark);
      transition: color 0.2s;
    }
    .nav-menu a:hover {
      color: var(--primary-red);
    }
    .nav-cta {
      background: var(--accent-orange);
      color: white !important;
      padding: 10px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background 0.2s, transform 0.2s;
    }
    .nav-cta:hover {
      background: #E55A2B;
      transform: scale(1.02);
      color: white !important;
    }
    .search-icon {
      font-size: 1.2rem;
      color: var(--secondary-gray);
      cursor: default;
      margin-left: 8px;
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      cursor: pointer;
      color: var(--text-dark);
    }
    @media (max-width: 840px) {
      .nav-menu {
        display: none;
      }
      .hamburger {
        display: block;
      }
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: white;
      flex-direction: column;
      padding: 32px 20px;
      gap: 24px;
      box-shadow: 0 10px 20px rgba(0,0,0,0.1);
      z-index: 49;
    }
    .mobile-menu.active {
      display: flex;
    }
    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 600;
    }

    /* 通用板块 */
    section {
      padding: var(--section-padding);
    }
    @media (max-width: 640px) {
      section {
        padding: var(--mobile-padding);
      }
    }

    .section-title {
      font-size: 36px;
      line-height: 1.25;
      margin-bottom: 16px;
      color: var(--text-dark);
    }
    .section-sub {
      color: #5f6368;
      font-size: 1.1rem;
      margin-bottom: 48px;
    }

    /* Hero */
    #hero {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      padding: 160px 0 120px;
      color: white;
      text-align: center;
    }
    #hero::before {
      content: '';
      position: absolute;
      top: 0; left: 0; width: 100%; height: 100%;
      background: rgba(0,0,0,0.55);
    }
    .hero-content {
      position: relative;
      z-index: 2;
    }
    .hero-title {
      font-size: 48px;
      line-height: 1.15;
      font-weight: 700;
      margin-bottom: 24px;
      color: white;
    }
    .hero-sub {
      font-size: 18px;
      color: rgba(255,255,255,0.85);
      margin-bottom: 40px;
      max-width: 700px;
      margin-left: auto;
      margin-right: auto;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-block;
      transition: background 0.2s, transform 0.2s;
      border: none;
    }
    .btn-primary:hover {
      background: #E55A2B;
      transform: scale(1.03);
      color: white;
    }
    @media (max-width: 640px) {
      .hero-title { font-size: 32px; }
    }

    /* 痛点卡片 */
    .pain-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    .pain-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: center;
    }
    .pain-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .pain-icon {
      font-size: 48px;
      color: var(--primary-red);
      margin-bottom: 20px;
      transition: transform 0.2s;
    }
    .pain-card:hover .pain-icon {
      transform: rotate(5deg);
    }
    @media (max-width: 840px) {
      .pain-grid { grid-template-columns: 1fr; }
    }

    /* 解决方案双栏 */
    .solution-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 80px;
    }
    .solution-row.reverse {
      flex-direction: row-reverse;
    }
    .solution-text {
      flex: 1;
    }
    .solution-img {
      flex: 1;
      border-radius: var(--radius-img);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
    }
    .solution-img img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    .check-list {
      list-style: none;
      padding: 0;
      margin: 24px 0 0;
    }
    .check-list li {
      margin-bottom: 12px;
      display: flex;
      align-items: flex-start;
    }
    .check-list i {
      color: var(--primary-red);
      margin-right: 12px;
      font-size: 1.2rem;
      margin-top: 4px;
    }
    @media (max-width: 840px) {
      .solution-row, .solution-row.reverse {
        flex-direction: column;
      }
    }

    /* 数据看板 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      text-align: center;
      background: var(--light-gray);
      padding: 48px 28px;
      border-radius: var(--radius-card);
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 56px;
      font-weight: 700;
      color: var(--accent-orange);
      line-height: 1.2;
    }
    @media (max-width: 640px) {
      .stats-grid { grid-template-columns: 1fr; }
      .stat-number { font-size: 40px; }
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 28px;
    }
    .testimonial-card {
      background: var(--card-bg);
      padding: 28px;
      border-radius: var(--radius-card);
      display: flex;
      flex-direction: column;
    }
    .quote-icon {
      color: var(--primary-red);
      font-size: 2rem;
      margin-bottom: 12px;
    }
    .testimonial-text {
      font-style: italic;
      margin-bottom: 20px;
      flex: 1;
    }
    .author {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .avatar {
      width: 48px;
      height: 48px;
      background: #ccc;
      border-radius: 50%;
      background-image: url('/assets/images/coverpic/cover-3.webp');
      background-size: cover;
    }
    @media (max-width: 640px) {
      .testimonial-grid { grid-template-columns: 1fr; }
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
    }
    .faq-question {
      font-weight: 700;
      font-size: 18px;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text-dark);
    }
    .faq-question span:first-child {
      color: var(--primary-red);
      margin-right: 12px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding-left: 24px;
      color: #4a4a4a;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }

    /* 最终CTA */
    #cta {
      background: var(--secondary-gray);
      color: white;
      text-align: center;
    }
    .btn-secondary {
      border: 2px solid white;
      color: white;
      padding: 12px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-block;
      margin-left: 16px;
      transition: 0.2s;
    }
    .btn-secondary:hover {
      background: white;
      color: var(--secondary-gray);
    }
    @media (max-width: 640px) {
      .btn-secondary { margin-left: 0; margin-top: 16px; }
    }

    /* 页脚 */
    .site-footer {
      background: #1e2127;
      color: #ccc;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      margin-bottom: 32px;
    }
    @media (max-width: 768px) {
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    .copyright {
      text-align: center;
      font-size: 14px;
      color: #888;
    }