/* roulang page: index */
:root {
      --primary: #1E3A2F;
      --primary-dark: #152B21;
      --accent: #F15A24;
      --accent-hover: #D94A1A;
      --bg-warm: #FAF9F6;
      --bg-light: #F5F7F6;
      --white: #FFFFFF;
      --text-main: #2C2C2C;
      --text-secondary: #555555;
      --text-muted: #777777;
      --text-light: #B0C5B8;
      --border-light: #E2E8E4;
      --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
      --shadow-card: 0 4px 20px rgba(0,0,0,0.06);
      --shadow-hover: 0 8px 30px rgba(0,0,0,0.12);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --font-title: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --transition: 0.25s ease-in-out;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-title);
      background-color: var(--bg-warm);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3, h4 {
      font-weight: 600;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: all var(--transition);
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(8px);
      z-index: 100;
      box-shadow: 0 2px 12px rgba(0,0,0,0.02);
      height: 72px;
      display: flex;
      align-items: center;
    }
    .header.scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.06);
    }
    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: -0.3px;
    }
    .logo i {
      font-size: 2rem;
      color: var(--accent);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-menu a {
      font-weight: 500;
      color: #333;
      font-size: 1rem;
      position: relative;
      padding: 4px 0;
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--accent);
      transition: width 0.2s;
    }
    .nav-menu a:hover {
      color: var(--accent);
    }
    .nav-menu a:hover::after {
      width: 100%;
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      white-space: nowrap;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
      border-color: var(--primary);
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      box-shadow: 0 4px 10px rgba(241,90,36,0.25);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      box-shadow: 0 8px 18px rgba(241,90,36,0.35);
      transform: translateY(-1px);
    }
    .hamburger {
      display: none;
      font-size: 1.8rem;
      background: none;
      border: none;
      color: var(--primary);
    }

    /* Hero */
    .hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      background: linear-gradient(135deg, #1E3A2F 0%, #0F231A 100%);
      position: relative;
      overflow: hidden;
      padding-top: 72px;
    }
    .hero::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.25;
      mix-blend-mode: overlay;
    }
    .hero-content {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 500px;
      color: white;
    }
    .hero-text h1 {
      font-size: 3.2rem;
      font-weight: 800;
      letter-spacing: -0.5px;
      line-height: 1.2;
      margin-bottom: 20px;
    }
    .hero-text .subtitle {
      font-size: 1.25rem;
      color: #C5D6CC;
      margin-bottom: 32px;
      max-width: 500px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-store {
      background: #111;
      color: white;
      padding: 12px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      display: flex;
      align-items: center;
      gap: 10px;
      border: 1px solid rgba(255,255,255,0.2);
    }
    .btn-store i {
      font-size: 1.8rem;
    }
    .btn-store:hover {
      background: #000;
      border-color: var(--accent);
    }
    .hero-mockup {
      flex: 1 1 380px;
      display: flex;
      justify-content: center;
      animation: float 6s ease-in-out infinite;
    }
    .hero-mockup img {
      max-height: 500px;
      border-radius: 32px;
      box-shadow: 0 25px 50px rgba(0,0,0,0.5);
    }
    @keyframes float {
      0% { transform: translateY(0px); }
      50% { transform: translateY(-12px); }
      100% { transform: translateY(0px); }
    }

    /* 通用板块 */
    .section {
      padding: 90px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 56px;
    }
    .section-title h2 {
      font-size: 2.2rem;
      font-weight: 700;
      color: var(--primary);
    }
    .section-title p {
      color: var(--text-secondary);
      margin-top: 12px;
      font-size: 1.1rem;
    }
    .grid-4 {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .card {
      background: var(--white);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      transition: all var(--transition);
      border: 1px solid var(--border-light);
    }
    .card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .icon-box {
      width: 64px;
      height: 64px;
      background: #E8F0EB;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--accent);
      font-size: 2rem;
    }
    .card h3 {
      font-size: 1.3rem;
      margin-bottom: 10px;
    }
    .card p {
      color: var(--text-secondary);
    }

    /* 交替图文 */
    .feature-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 80px;
      flex-wrap: wrap;
    }
    .feature-img {
      flex: 1 1 400px;
    }
    .feature-img img {
      border-radius: 24px;
      box-shadow: var(--shadow-card);
    }
    .feature-text {
      flex: 1 1 400px;
    }
    .feature-text h3 {
      font-size: 1.8rem;
      margin-bottom: 20px;
      color: var(--primary);
    }
    .feature-list {
      list-style: none;
    }
    .feature-list li {
      margin-bottom: 14px;
      display: flex;
      gap: 10px;
      color: var(--text-secondary);
    }
    .feature-list i {
      color: var(--accent);
      margin-top: 4px;
    }

    /* 数据卡 */
    .stats-grid {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 24px;
      text-align: center;
    }
    .stat-item {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-md);
      min-width: 180px;
      box-shadow: var(--shadow-sm);
    }
    .stat-number {
      font-size: 3.2rem;
      font-weight: 800;
      color: var(--accent);
      line-height: 1.2;
    }

    /* FAQ */
    .faq-item {
      background: var(--bg-light);
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      background: #F5F7F6;
    }
    .faq-answer {
      padding: 0 20px 20px;
      color: #444;
      display: none;
      background: white;
    }
    .faq-item.active .faq-answer {
      display: block;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA 下载 */
    .cta-section {
      background: linear-gradient(135deg, #1E3A2F, #152B21);
      color: white;
      text-align: center;
    }
    .cta-buttons {
      display: flex;
      justify-content: center;
      gap: 20px;
      flex-wrap: wrap;
      margin-top: 28px;
    }

    /* 页脚 */
    .footer {
      background: var(--primary);
      color: var(--text-light);
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }
    .footer a:hover {
      color: var(--accent);
    }
    .copyright {
      background: var(--primary-dark);
      text-align: center;
      padding: 16px;
      font-size: 0.9rem;
      color: #8DA399;
    }

    @media (max-width: 1024px) {
      .grid-4 { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 768px) {
      .hamburger { display: block; }
      .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background: var(--primary);
        flex-direction: column;
        padding: 80px 30px;
        gap: 24px;
        transition: 0.3s;
      }
      .nav-menu.active { right: 0; }
      .nav-menu a { color: white; }
      .grid-4, .grid-3 { grid-template-columns: 1fr; }
      .hero-content { flex-direction: column; text-align: center; }
      .hero-text h1 { font-size: 2.4rem; }
      .feature-row { flex-direction: column; }
      .footer-grid { grid-template-columns: 1fr; }
    }