/* roulang page: index */
:root {
      --primary: #E8451E;
      --primary-dark: #C93A18;
      --primary-light: #FDECEA;
      --secondary: #1C1C1C;
      --accent: #FFB800;
      --bg-warm: #F9F7F4;
      --white: #FFFFFF;
      --text-main: #1C1C1C;
      --text-body: #3A3A3A;
      --text-muted: #6B6B6B;
      --text-light: #B0B0B0;
      --border-light: #E8E8E8;
      --border-input: #D0D0D0;
      --success: #2EAD6F;
      --radius-card: 12px;
      --radius-btn: 8px;
      --shadow-card: 0 8px 24px rgba(0,0,0,0.05);
      --shadow-card-hover: 0 12px 28px rgba(0,0,0,0.1);
      --shadow-nav: 0 2px 12px rgba(0,0,0,0.06);
      --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --max-width: 1200px;
      --header-height: 72px;
      --header-height-mobile: 56px;
      --section-gap: 100px;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-warm);
      color: var(--text-body);
      line-height: 1.65;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: transparent;
      z-index: 1000;
      transition: background 0.25s ease, box-shadow 0.25s ease, height 0.2s;
      display: flex;
      align-items: center;
    }

    .header.scrolled {
      background: var(--white);
      box-shadow: var(--shadow-nav);
      height: var(--header-height);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-family: var(--font-heading);
      font-weight: 800;
      font-size: 1.8rem;
      color: var(--white);
      letter-spacing: 1px;
      text-decoration: none;
      white-space: nowrap;
      transition: color 0.25s;
    }

    .header.scrolled .logo {
      color: var(--secondary);
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-links a {
      text-decoration: none;
      font-weight: 500;
      color: rgba(255,255,255,0.9);
      font-size: 0.95rem;
      transition: color 0.2s;
      position: relative;
    }

    .header.scrolled .nav-links a {
      color: var(--text-body);
    }

    .nav-links a:hover {
      color: var(--primary);
    }

    .nav-cta {
      background: var(--primary);
      color: white !important;
      padding: 10px 22px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background 0.2s, transform 0.2s;
      display: inline-block;
    }

    .nav-cta:hover {
      background: var(--primary-dark);
      transform: translateY(-1px);
    }

    .burger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
      z-index: 1001;
    }

    .burger span {
      width: 26px;
      height: 2.5px;
      background: var(--white);
      border-radius: 4px;
      transition: 0.3s;
      display: block;
    }

    .header.scrolled .burger span {
      background: var(--secondary);
    }

    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: var(--white);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      transform: translateX(100%);
      transition: transform 0.35s cubic-bezier(0.23, 1, 0.32, 1);
      z-index: 999;
      list-style: none;
    }

    .mobile-menu.active {
      transform: translateX(0);
    }

    .mobile-menu a {
      font-size: 1.5rem;
      font-weight: 600;
      color: var(--secondary);
      text-decoration: none;
    }

    /* Hero */
    .hero {
      min-height: 90vh;
      background: linear-gradient(180deg, rgba(28,28,28,0.55) 0%, rgba(28,28,28,0.2) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      display: flex;
      align-items: center;
      color: white;
      position: relative;
    }

    .hero-content {
      max-width: 700px;
      padding-top: 80px;
    }

    .hero h1 {
      font-size: clamp(2.5rem, 7vw, 3.8rem);
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 1.5rem;
      color: white;
    }

    .hero-sub {
      font-size: 1.2rem;
      color: #E0E0E0;
      margin-bottom: 2.5rem;
      max-width: 550px;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      border: none;
      cursor: pointer;
      font-size: 1rem;
      text-decoration: none;
      display: inline-block;
      transition: background 0.2s, box-shadow 0.2s;
    }

    .btn-primary:hover {
      background: var(--primary-dark);
      box-shadow: 0 8px 18px rgba(232,69,30,0.3);
    }

    /* 通用板块 */
    .section {
      padding: var(--section-gap) 0;
    }

    .section-title {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 1rem;
      text-align: center;
    }

    .section-desc {
      color: var(--text-muted);
      text-align: center;
      max-width: 650px;
      margin: 0 auto 3rem;
    }

    /* 痛点卡片 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .pain-card {
      background: var(--white);
      padding: 28px 24px;
      border-radius: var(--radius-card);
      border-left: 4px solid transparent;
      transition: all 0.25s;
      box-shadow: var(--shadow-card);
    }

    .pain-card:hover {
      border-left-color: var(--primary);
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-4px);
    }

    .pain-icon {
      font-size: 2rem;
      margin-bottom: 16px;
      color: var(--primary);
    }

    .pain-card h3 {
      font-weight: 700;
      margin-bottom: 10px;
      color: var(--secondary);
    }

    /* 解决方案卡片 */
    .solution-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 32px;
    }

    .solution-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: 0.2s;
    }

    .solution-card:hover {
      box-shadow: var(--shadow-card-hover);
    }

    .solution-img {
      width: 100%;
      height: 220px;
      object-fit: cover;
    }

    .solution-text {
      padding: 24px;
    }

    .solution-text h3 {
      font-weight: 700;
      margin-bottom: 8px;
      color: var(--secondary);
    }

    /* 数据块 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      text-align: center;
    }

    .stat-item {
      background: var(--white);
      padding: 32px 16px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }

    .stat-number {
      font-size: 2.8rem;
      font-weight: 800;
      color: var(--primary);
      line-height: 1.2;
    }

    .stat-label {
      color: var(--text-muted);
      margin-top: 8px;
      font-weight: 500;
    }

    /* 证言 */
    .testimonial-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }

    .testimonial-card {
      background: var(--white);
      padding: 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }

    .quote {
      font-style: italic;
      font-size: 1.05rem;
      margin-bottom: 20px;
    }

    .user {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #ddd;
      object-fit: cover;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }

    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      padding: 20px 0;
      font-weight: 600;
      font-size: 1.1rem;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      text-align: left;
      color: var(--secondary);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-body);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 18px;
    }

    /* CTA 区 */
    .cta-section {
      background: var(--secondary);
      color: white;
      text-align: center;
      padding: 80px 0;
      border-radius: 24px 24px 0 0;
      margin-top: 40px;
    }

    .cta-section h2 {
      font-size: 2.2rem;
      margin-bottom: 1rem;
    }

    /* 页脚 */
    .footer {
      background: var(--secondary);
      color: var(--text-light);
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    .footer a {
      color: var(--text-light);
      text-decoration: none;
    }

    .copyright {
      border-top: 1px solid #333;
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
      font-size: 0.9rem;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .grid-3, .testimonial-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .solution-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .burger { display: flex; }
      .header { height: var(--header-height-mobile); }
      .grid-3, .testimonial-grid, .stats-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero h1 { font-size: 2.5rem; }
      .section { padding: 60px 0; }
    }