/* roulang page: index */
:root {
      --primary: #1A1A1A;
      --accent: #D4AF37;
      --accent-hover: #C2A34F;
      --bg: #FAFAFA;
      --card-bg: #FFFFFF;
      --alt-bg: #F5F3EF;
      --text-primary: #1A1A1A;
      --text-body: #4A4A4A;
      --text-muted: #8A8A8A;
      --border-light: #EBEBEB;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06);
      --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
      --radius-card: 4px;
      --radius-btn: 2px;
      --font-stack: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-stack);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 40px;
    }
    @media (max-width: 1024px) {
      .container {
        padding: 0 32px;
      }
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }
    /* 导航栏 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 64px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 0 40px;
      z-index: 50;
      transition: background 0.3s ease, backdrop-filter 0.3s ease;
      background: transparent;
    }
    .navbar.scrolled {
      background: rgba(26, 26, 26, 0.85);
      backdrop-filter: blur(8px);
    }
    .nav-links a {
      color: var(--text-primary);
      font-weight: 500;
      margin-right: 28px;
      transition: color 0.2s;
    }
    .navbar.scrolled .nav-links a {
      color: #FAFAFA;
    }
    .nav-links a:hover {
      color: var(--accent);
    }
    .nav-cta-btn {
      background: var(--accent);
      color: var(--primary) !important;
      padding: 8px 24px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: background 0.25s;
      white-space: nowrap;
    }
    .nav-cta-btn:hover {
      background: var(--accent-hover);
    }
    .hamburger {
      display: none;
      font-size: 24px;
      color: var(--primary);
      cursor: pointer;
    }
    .navbar.scrolled .hamburger {
      color: #FAFAFA;
    }
    @media (max-width: 768px) {
      .nav-links, .nav-cta-btn {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .navbar {
        padding: 0 20px;
      }
      .mobile-menu {
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: var(--primary);
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 2rem;
        z-index: 40;
        transform: translateX(100%);
        transition: transform 0.3s ease;
      }
      .mobile-menu.open {
        transform: translateX(0);
      }
      .mobile-menu a {
        color: #FAFAFA;
        font-size: 1.5rem;
        font-weight: 500;
      }
      .mobile-menu .close-btn {
        position: absolute;
        top: 20px;
        right: 20px;
        font-size: 28px;
        color: #FAFAFA;
      }
    }
    /* Hero 分屏 */
    .hero-split {
      display: flex;
      min-height: 100vh;
      align-items: center;
    }
    .hero-left {
      width: 55%;
      padding-right: 60px;
    }
    .hero-right {
      width: 45%;
      height: 100vh;
      position: relative;
      overflow: hidden;
    }
    .hero-right img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .hero-right::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: linear-gradient(to right, rgba(250,250,250,0.7) 0%, rgba(250,250,250,0) 40%);
    }
    @media (max-width: 768px) {
      .hero-split {
        flex-direction: column;
      }
      .hero-left, .hero-right {
        width: 100%;
      }
      .hero-right {
        height: 45vh;
      }
      .hero-left {
        padding-right: 0;
        padding: 40px 0;
      }
    }
    /* 动画 */
    .fade-up {
      opacity: 0;
      transform: translateY(20px);
      transition: opacity 0.6s ease-out, transform 0.6s ease-out;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }
    .card-hover {
      transition: box-shadow 0.25s, transform 0.25s, border-left 0.2s;
      border-left: 3px solid transparent;
    }
    .card-hover:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
      border-left: 3px solid var(--accent);
    }
    .btn-primary {
      background: var(--accent);
      color: var(--primary);
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      transition: background 0.25s;
    }
    .btn-primary:hover {
      background: var(--accent-hover);
    }
    .btn-secondary {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 14px 36px;
      border-radius: var(--radius-btn);
      display: inline-block;
      transition: 0.25s;
    }
    .btn-secondary:hover {
      background: var(--primary);
      color: #FAFAFA;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      overflow: hidden;
    }
    .faq-content {
      max-height: 0;
      transition: max-height 0.35s ease-in-out;
    }
    .faq-content.open {
      max-height: 200px;
    }
    .arrow-icon {
      transition: transform 0.3s;
    }
    .arrow-icon.rotate {
      transform: rotate(180deg);
    }
    .count-up {
      font-variant-numeric: tabular-nums;
      font-feature-settings: "tnum";
      font-weight: 300;
    }
    input, textarea {
      border: none;
      border-bottom: 1px solid var(--accent);
      background: transparent;
      padding: 12px 4px;
      width: 100%;
      outline: none;
      transition: border 0.2s;
      font-family: var(--font-stack);
    }
    input:focus, textarea:focus {
      border-bottom: 2px solid var(--accent-hover);
    }