/* roulang page: index */
:root {
      --euler-green: #1A2E1F;
      --euler-green-deep: #142618;
      --sand-gold: #C4A265;
      --sand-dark: #A88A4A;
      --warm-gray: #F5F3EF;
      --deep-rock: #1C1C1C;
      --text-primary: #1C1C1C;
      --text-secondary: #5A5A5A;
      --text-muted: #8A8A8A;
      --white: #FFFFFF;
      --brick-red: #B14B3C;
      --border-light: rgba(0, 0, 0, 0.06);
      --shadow-sm: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-card: 8px;
      --radius-btn: 4px;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      --max-width: 1280px;
      --space-unit: 8px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      background-color: var(--warm-gray);
      color: var(--text-primary);
      font-family: 'PingFang SC', 'Noto Sans SC', 'Microsoft YaHei', 'Helvetica Neue', system-ui, -apple-system, sans-serif;
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
    }
    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      transition: background 0.3s, backdrop-filter 0.3s;
      background: rgba(245, 243, 237, 0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 32px;
      height: 72px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 12px;
    }
    .logo-text {
      font-size: 24px;
      font-weight: 700;
      letter-spacing: -0.02em;
      color: var(--euler-green);
      position: relative;
    }
    .logo-line {
      width: 42px;
      height: 2px;
      background: var(--sand-gold);
      display: inline-block;
      margin-left: 8px;
      vertical-align: middle;
    }
    .nav-menu {
      display: flex;
      gap: 40px;
      list-style: none;
      align-items: center;
    }
    .nav-menu a {
      font-weight: 500;
      color: var(--text-secondary);
      font-size: 16px;
      position: relative;
      transition: color 0.2s;
    }
    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--euler-green);
    }
    .nav-menu a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--sand-gold);
      transition: width 0.2s;
    }
    .nav-menu a:hover::after,
    .nav-menu a.active::after {
      width: 100%;
    }
    .btn-primary {
      background: var(--euler-green);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 8px;
      transition: background 0.2s, transform 0.2s;
      font-size: 15px;
      white-space: nowrap;
    }
    .btn-primary:hover {
      background: var(--euler-green-deep);
      transform: translateX(2px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--euler-green);
      color: var(--euler-green);
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: 0.2s;
    }
    .btn-outline:hover {
      background: rgba(26,46,31,0.06);
    }
    .mobile-toggle {
      display: none;
      background: none;
      font-size: 28px;
      color: var(--euler-green);
    }
    /* 底部胶囊 mobile 备选⻛格，隐藏桌面 */
    .mobile-bottom-nav {
      display: none;
    }

    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      padding: 120px 0 80px;
      background: var(--warm-gray);
      position: relative;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 80px;
      flex-wrap: wrap;
    }
    .hero-content {
      flex: 1 1 45%;
    }
    .hero-title {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.1;
      letter-spacing: -0.02em;
      color: var(--euler-green);
      margin-bottom: 24px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 40px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .hero-visual {
      flex: 1 1 45%;
      background: linear-gradient(135deg, rgba(26,46,31,0.7) 0%, rgba(20,38,24,0.5) 100%), url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 24px;
      height: 400px;
      box-shadow: 0 20px 35px rgba(0,0,0,0.15);
      position: relative;
      overflow: hidden;
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: 40px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 16px;
      color: var(--text-primary);
    }
    .section-sub {
      color: var(--text-secondary);
      margin-bottom: 48px;
      font-size: 17px;
    }

    /* 优势 非对称 */
    .advantages-grid {
      display: flex;
      flex-direction: column;
      gap: 100px;
    }
    .advantage-row {
      display: flex;
      align-items: center;
      gap: 64px;
      flex-wrap: wrap;
    }
    .adv-text {
      flex: 1;
    }
    .adv-media {
      flex: 1;
      background: #ddd8cc;
      border-radius: var(--radius-card);
      overflow: hidden;
      height: 300px;
    }
    .adv-media img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .adv-icon {
      color: var(--sand-gold);
      font-size: 28px;
      margin-bottom: 16px;
    }
    .adv-title {
      font-size: 28px;
      font-weight: 700;
      margin-bottom: 14px;
    }
    .reverse {
      flex-direction: row-reverse;
    }

    /* 场景卡片 */
    .scene-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
    }
    .scene-card {
      background: white;
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
    }
    .scene-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .scene-img {
      height: 200px;
      background: #d9d2c0;
      overflow: hidden;
    }
    .scene-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
      transition: transform 0.4s;
    }
    .scene-card:hover .scene-img img {
      transform: scale(1.04);
    }
    .scene-info {
      padding: 28px;
    }
    /* 案例墙数字 */
    .stats-row {
      display: flex;
      justify-content: center;
      gap: 80px;
      margin: 60px 0 50px;
      flex-wrap: wrap;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--sand-gold);
      font-family: 'DIN Alternate', 'Inter', sans-serif;
    }
    .logo-wall {
      display: flex;
      overflow-x: auto;
      gap: 48px;
      padding: 20px 0;
      filter: grayscale(100%);
      opacity: 0.7;
    }

    /* 价格 */
    .pricing-grid {
      display: flex;
      gap: 30px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .pricing-card {
      background: white;
      padding: 40px;
      border-radius: 16px;
      flex: 1 1 280px;
      box-shadow: var(--shadow-sm);
      transition: 0.25s;
      position: relative;
    }
    .pricing-card.popular {
      border: 2px solid var(--sand-gold);
      transform: scale(1.03);
      box-shadow: var(--shadow-hover);
    }
    /* faq */
    .faq-layout {
      display: flex;
      gap: 64px;
    }
    .faq-left {
      min-width: 140px;
    }
    .faq-tag {
      display: block;
      padding: 10px 15px;
      margin-bottom: 8px;
      border-radius: 20px;
      background: #e4ded2;
    }
    .accordion-item {
      border-bottom: 1px solid #ddd;
      padding: 18px 0;
    }

    footer {
      background: var(--deep-rock);
      color: #ccc;
      padding: 70px 0 20px;
    }
    footer a {
      color: #aaa;
    }
    @media (max-width: 1024px) {
      .hero-title { font-size: 44px; }
      .hero .container { gap: 40px; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .mobile-toggle { display: block; }
      .hero .container { flex-direction: column; text-align: center; }
      .hero-title { font-size: 36px; }
      .scene-grid { grid-template-columns: 1fr; }
      .advantage-row, .reverse { flex-direction: column; }
      .adv-media { width: 100%; }
    }
    @media (max-width: 520px) {
      .hero-buttons { justify-content: center; }
-左侧保留用`